# W12 Tire Pressures, Ride Comfort and Road Noise



## PanEuropean (Nov 3, 2001)

Hi All:
A few months ago, while poking around my VW dealer in Zürich, I found a W12 LWB Phaeton that was similar to the Phaeton I own in Canada. I had a look at the tire pressure sticker on the car, and noted that it provided pressure information for both half load and full load configurations, same as my 2002 Golf did. I also noted that for the exact same size and load bearing classification of tire, the European Phaeton had much lower tire pressures specified.
When I returned to Canada, I had a second look at the tire pressure sticker on my car, and saw that it only provided pressures for a 'full load' configuration (in other words, assuming that my Phaeton was loaded to full capacity, with 968 pounds of payload), and even then, the pressures specified were much higher than the pressures specified for a fully loaded European Phaeton.
Being aware, from other posts, that North American Phaetons have a slightly higher suspension setting (ride height) to allow for poorer road surfaces in North America, I kind of figured that maybe our tire pressures have been jacked up for the same reason - to increase ground clearance, and provide better impact protection when we hit potholes. The roads around my city are 'reasonable' - not up to European standards, but generally fairly well kept, no big potholes with tow trucks waiting at the bottom of them - so, I thought I would try using the lower European tire pressures and see if it made a difference. Because I rarely carry passengers in the back seat, and don't carry any cargo other than the odd bag of groceries, I set the front tires of my car to 38 PSI, and the rear tires to 35 PSI, exactly as is specified for the European Phaeton with the same tires. This is quite a drop from the 42 and 48 PSI specified for the North American Phaeton.
After about 500 km (300 miles) of driving in the past week, I have found that the ride of the Phaeton is a bit softer, and the tire noise is much less noticeable with the lower pressures. I'm still not sure if there is any other reason that explains the difference in pressure specifications, but, for the time being, I am quite happy with the results of using the lower pressures, and I intend to leave the tires at the lower European specification pressures.
Michael
*W12 Tire Pressure Sticker - North America*








*W12 Short Wheelbase Tire Pressure Sticker - Europe*
_Note that our North American cars have the 255/45 tires on them, which is the lower of the two sets specified in the sticker below._








*European W12 Long Wheelbase Tire Sticker*


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Michael,
As I was telling you last night on the phone, my tire pressures are headed down that way naturally. I'll just keep resetting my TPM each time low pressure messages comes on.







They dropped 3 pounds in a month.


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## Paldi (Sep 4, 2004)

Michael....

Several of the reviews mentioned ride harshness or suspension non-compliance at low speeds. Do you think this was due to the air pressure of the tires?
I notice a big difference between the recommended pressures for 17 inch and 18 inch tires. Do you have the suggested values for 19 inch tires used, for example, with the Helios wheels?
_Modified by Paldi at 9:02 AM 2-7-2005_


_Modified by Paldi at 7:07 PM 5-21-2005_


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## whealy (Nov 15, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Michael,
Good information as always.
isn't the trade off between high and low preasuer better wear on the tires as opposed to better ride? Perhapse VW north America simply puts more emphasis on the wear as they beleive the ride difference is minimal with the Phaeton.


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## Jack Orr (Mar 15, 2000)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Michael, this tire pressure thing has been bugging me all along. I have never owned a car with these kind of recommended tire pressures.
When summer comes in Texas, a long high speed trip would put the pressures at astronomical levels if they started at the recommended psi when cold.
Your post will make me feel more confidant when I reduce pressure later on.
Jack


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## PanEuropean (Nov 3, 2001)

*Re: (Paldi)*


_Quote, originally posted by *Paldi* »_ Do you have the suggested values for 19 inchers?

No - I have not investigated what the VW recommended pressures are for the Phaetons that ship from the factory with 19 inch wheels (e.g. Omaynt, Helios). My interest was focused mostly on the differences in the recommended pressure for the same vehicle, equipped with the same tire size and load capacity tires on either side of the Atlantic.
Normally, I am pretty conservative about following manufacturer recommendations for tire fitment and inflation pressure. What caught my attention here is that we have two different specifications for the same vehicle and equipment configuration, and there does not seem to be an obvious reason for the difference. I've speculated that a possible reason might be the importer's concern about tire or rim damage on poorly maintained roads. The main reason I made the post here on the public forum was to solicit additional information from others who might be better informed about this - for example, Eric from 'The Tire Rack', who is the moderator of the tire forum here on Vortex.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: (Paldi)*

I didn't have any complaints about the ride of the car with the original (North American) tire pressure settings. I have observed that there is less road noise, and less intrusion from road defects (e.g. tar strips) now that I am using the lower pressure settings.
Michael


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## av_audi (Apr 5, 2001)

I am surprised the payload capacity of such a large car is only 968lbs. But I guess if you count all the goodies that are already stuffed in it, it adds up to quite a lot of "fixed payload"








In any case, I am also surprised the U.S. Phaeton doesn't come with the typical four pressure recommendations of VW resulting from half/full load and under/over 100mph combinations. (For Germany, they probably only use list the over 100mph recommendation







) The reduced 4 psi in the front will increase steering weight but it will also reduce turn in sharpness somewhat. You can always experiment with what you like best. For the rears though, the tremendous difference in pressure will make a world of difference for the comfort of rear passengers. Front passengers won't feel the difference as much, but I can tell you that the one time I had to inflate my Passat's rear tires to 42-43psi because I had about 900lbs in the trunk, after unloading the wiehgt, the rear felt like that of a truck. You don't feel it that much, but you can tell it is bouncing and dancing over every ripple on the road.


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## Paldi (Sep 4, 2004)

*Re: (av_audi)*

The reduction in turn-in sharpness is the drawback of reducing front tire pressure. I don't expect it to be much of a difference with only a 4 pound reduction in pressure.
Is there a wheel and tire Forum you frequent that's any good, aside from Tire Rack?

_Modified by Paldi at 9:07 AM 2-7-2005_



_Modified by Paldi at 7:07 PM 5-21-2005_


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## PanEuropean (Nov 3, 2001)

*Re: (av_audi)*


_Quote, originally posted by *av_audi* »_I am surprised the payload capacity of such a large car is only 968lbs.

So was I. I think the regulations governing load capacity calculations for North America have changed recently. The load capacity for the very same Phaeton, in Europe, is higher. My guess is that the new calculation methodology for North America assumes that the car is fully loaded with every possible option, and has a full tank of fuel at all times.

_Quote, originally posted by *av_audi* »_I am also surprised the U.S. Phaeton doesn't come with the typical four pressure recommendations of VW resulting from half/full load...

Again, my thoughts exactly - I think I remarked about that in my original post at the top of the thread. My 2002 Golf tire pressure specification sticker gave pressures for both full and half loads, and so do the stickers on Phaetons sold in Europe. Which leads me to believe that the change is also due to some form of government regulation, rather than any desire to change on the part of Volkswagen.
Michael


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## av_audi (Apr 5, 2001)

*Re: (Paldi)*


_Quote, originally posted by *Paldi* »_Is there a wheel and tire Forum you frequent that's any good?

Just in case you missed my reply to you in the wheel forum, which you had already found before I even looked for it, Load capacity
_URL formatting corrected, text untouched. Michael_


_Modified by PanEuropean at 11:31 PM 2-4-2005_


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## av_audi (Apr 5, 2001)

*Re: (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_ I think I remarked about that in my original post 

You did. Something may haveindeed changed, because I vaguely remember owners of 04/05 Passats reporting that only two pressure recommendations are listed instead of four for previous year models. But we still have only one for the Phaeton in the U.S. I would be curious to know the story behind this.


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## move.over (Nov 25, 2004)

*Re: (av_audi)*

04.5 4Motion Passat has only one type recommended but different front and rear, from memory 40 front 45 rear. Never had a car that required such high pressure. Might have to do something with the fuel mileage numbers and corporate CAFE. Maybe with the Touraq and Phateon in the mix VW was not getting the numbers required?


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## av_audi (Apr 5, 2001)

*Re: (move.over)*


_Quote, originally posted by *move.over* »_04.5 4Motion Passat has only one type recommended but different front and rear, from memory 40 front 45 rear. Never had a car that required such high pressure. Might have to do something with the fuel mileage numbers and corporate CAFE. Maybe with the Touraq and Phateon in the mix VW was not getting the numbers required?

There must be something strange going on here. If memory serves me right, my 1.8T's pressure recommendation for over 100mph with full load (almost 1100lbs) is around 33F/42R. For half-load and less than 100mph, the recommendation is only 28F/28R (too soft for me), which goes up only to 30F/28R for over 100mph. I often run 32F/31R when it's only me in the car, and 40F/45R would feel incredibly harsh! Anything above 35psi already feels quite harsh.
Changing from a 28/28 recommendation for the typical way in which this car is driven to a default 40/45 recommendation is simply insane. But then again, VW just changed the oil change requirements for this engine (filter and oil) SIX years after it's been in use in production cars. Also, it is not uncommon to find two to three different specs for this car depending on which VW document you look at. Accurate and consistent documentation is not a VW forte, at least for their U.S. bound littereature.
I wonder how prematurely shocks and steering components are going to wear out with the constant severe pounding resulting from these extremely high tire pressures.


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## move.over (Nov 25, 2004)

*Re: (av_audi)*

Ok you made me look







, memory is getting bad http://****************.com/smile/emthdown.gif , the actual numbers are 36/44, still high in my opinion and I run them at a lower number.
The reason for the higher numbers on the back might be because of the different suspension used on 4-Motion cars.


_Modified by move.over at 2:55 PM 2-4-2005_


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## av_audi (Apr 5, 2001)

I actually started a thread about the new high pressure recommendation on the B5 forum, and member Altair4 stated: _New NHSTA regulation. Vehicle manufacturers are only permitted to post one and only one pressure setting - the maximum speed and load setting. And yes, I'm sure we can all thank that Ford/Firestone fiasco for this one._
_Addition by Michael:_ Here's the link to AV Audi's thread on the Passat forum: VW tire pressure recommendation very different for 2005 models?


_Modified by PanEuropean at 12:04 AM 2-5-2005_


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## PanEuropean (Nov 3, 2001)

*Re: (av_audi)*

Ah-ha - that explains it. Thanks very much for providing that information. I now feel much more at ease following the VW European tire pressure recommendations. I can only presume that because VW is only allowed to publish one tire pressure - which must, obviously, be suitable for the worst possible operating condition (maximum gross weight), they are publishing the highest possible pressure setting.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: (av_audi)*


_Quote, originally posted by *av_audi* »_I am surprised the payload capacity of such a large car is only 968 lbs _(439 kg)_. But I guess if you count all the goodies that are already stuffed in it, it adds up to quite a lot of "fixed payload"...

Just coming back to this observation that AV Audi made earlier in the thread - now that we have determined that the single, very high tire pressure recommendation for North American Phaetons is a result of the US Government knowing more about vehicle safety than the manufacturer of the car







, perhaps it is worth taking a closer look at the payload restriction imposed on the Phaetons in the United States market area (which, regrettably, encompasses Canada as well - this being a VW policy decision).
The load placard on my 2004 W12 LWB Phaeton is shown above, and states that the maximum payload is 439 kg (968 lbs). However, this same car has a gross vehicle weight rating (GVWR) of 2910 kg (6,415 lbs), as indicated by the import compliance sticker on the front portion of the driver door aperture.
The GVWR of 2910 kg shown corresponds to the 'Gross Vehicle Weight' (the European Community term for the same thing) of 2,910 kg that is published in the technical data for the Phaeton distributed in Germany. However - that same German technical data lists the empty weight of the vehicle as being anywhere between 2,363 and 2,468 kg, depending on what options are fitted at the time of manufacture. This yields payloads ranging from 547 kg to 442 kg (1,205 lbs to 974 lbs), again, depending on what options have been embodied at the time of manufacture.
Although my W12 is fairly well kitted out, I can think of a whole lot of options that I don't have on my car, and without any doubt, all the options that I don't have (larger starter battery, DVD passenger entertainment, TV tuner, fridge, ADR cruise control, extended leather, stand-heating, cell phone, paddle shifters, 18 way front passenger seat, just to name a few) would easily add 100 kg to the basic operating weight of my car.
In Europe, payloads for vehicles are calculated in exactly the same manner as payloads for aircraft: the automobile manufacturer provides you with the exact scale weight of your unladen vehicle, this weight is listed in the automobile registration documents, along with the gross allowable vehicle weight. It's pretty simple math to figure out what your payload then is.
How VW came up with a payload restriction of 439 kg for a vehicle that the manufacturer declares will have a minimum allowable payload of 442 kg when it is loaded with every possible option is beyond my comprehension - however, I kind of suspect it has to do with the general 'dumbing down' process that is imposed on vehicle manufacturers by governments over here.
Michael
*GVWR Sticker - Canadian W12*


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## PanEuropean (Nov 3, 2001)

*Re: (PanEuropean)*

Here are a few links that provide some background information about the recent changes in American law related to vehicle tire pressures.
A rather scholarly document, the NHTSA Tire Pressure Special Study, conclude that only 8% of American drivers pay any attention at all to the tire pressure placard provide on their vehicle.
A notice of proposed rule-making (NPRM) respecting Tire Pressure Monitoring Systems found that substantial fuel economy benefits would be gained if average nationwide tire pressures were increased.
Despite doing about an hour's worth of searching of the NHTSA and US CFR databases, I have been unable to find the text of the new (i.e. changed) regulation concerning tire pressure placards in cars. Perhaps someone else who is more familiar with US law might want to go looking for this. Here are a few links worth starting from: NHTSA Safety Standards - Home Page, and NHTSA Safety Rulemaking Priorities, 2003 through 2006.
Michael


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## tjl (Mar 24, 2001)

*Re: (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_Here are a few links that provide some background information about the recent changes in American law related to vehicle tire pressures.
A rather scholarly document, the NHTSA Tire Pressure Special Study, conclude that only 8% of American drivers pay any attention at all to the tire pressure placard provide on their vehicle.


Don't forget the Ford Explorer / Firestone Wilderness AT fiasco a few years back. With a low recommended tire pressure, the low end tires on the heavy SUV had little margin of safety against dangerous underinflation. So NHTSA and car companies are probably being more conservative about tire pressures (i.e. only recommending higher full load pressures to give more margin of safety against dangerous underinflation due to the owner not checking the tire pressure often enough).


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## move.over (Nov 25, 2004)

*Re: (PanEuropean)*

Michael,
SEMA has a good write-up showing all the different items as a result of TREAD including the new labeling, TIN, Pressure monitoring Systems etc. Love those federal people and their abbreviations








http://www.sema.org/main/semaorghome.aspx?id=52521


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## PanEuropean (Nov 3, 2001)

*Re: (move.over)*

Hello Jan:
Thanks very much for doing the work to find that reference article. What I am still looking for (not that I want to sound ungrateful in any way for the work you have already done!) is the specific details of the new 'defined format' - the one with the September, 2003 introduction date - that governs the changes to the tire pressure placard. Below is a quote from the website you referenced above that mentions this briefly:
_"...automakers were required to place the tire inflation/load limit placard on the driver's side post by September 2003, using a defined format. Automakers must also provide more tire safety information, including a discussion of correct tire inflation in owner's manuals."_
FWIW, it should be pretty easy to spot VW products that conform with this new regulation - VW's practice prior to the introduction of this rule was to put the tire inflation specification placard on the fuel cap door flap.
Michael


_Modified by PanEuropean at 5:06 PM 2-5-2005_


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## move.over (Nov 25, 2004)

*Re: (PanEuropean)*

I had found that document too, but thought it was too technical for the forum and thought the Sema provided a pretty good overview.
Here is the document you are looking for:
http://www.nhtsa.gov/cars/rule....html


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## PanEuropean (Nov 3, 2001)

*Re: (move.over)*

Jan:
You are a gentleman and a scholar; that is exactly what I was looking for. 
My particular judicial specialty is the Geneva Conventions and their additional protocols, if you ever need the favour returned, let me know.
Michael


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## av_audi (Apr 5, 2001)

*Re: (move.over)*


_Quote, originally posted by *move.over* »_
Here is the document you are looking for:
http://www.nhtsa.gov/cars/rule....html

Thanks for the link. This document should be subtitled "Your tax dollars at work."
Just glancing it over makes you go


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## PassatWheels (Feb 22, 1999)

*Re: (av_audi)*


_Quote, originally posted by *av_audi* »_
This document should be subtitled "Your tax dollars at work."
Just glancing it over makes you go









I think it reads like that in part because of the powerful automotive lobby that makes the government parse every word six ways from Sunday to ensure that no regulation intended to protect the consumer is ever promulgated.
Many people take these reports at face value just because they *sound like* they know what they're talking about.
Or as Kevin Coster said in JFK: "the Government would have you believe that an elelphant can hang from a cliff with his tail tied to a daisy..."


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## PanEuropean (Nov 3, 2001)

*Re: (PanEuropean)*

So, it seems, the final answer to the original question is this:
Referring to the two pictures at the very top of this thread - the content, design, the font size and style, and even the diagram of the little tire on the North American sticker is entirely the work of the US NHTSA. All VW was allowed to do was to fill in pressures, which must be the highest possible pressures under any circumstances, because the government only allows VW to specify one pressure setting.
The second sticker - the European one - is entirely the work of the engineers at Volkswagen in Europe, and gives you VW's recommendation for the tire pressures, without the benefit of any government advice on the subject. It's up to you to choose which organization to place your trust in.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: (PanEuropean)*

Just a post-script here, in case anyone reads this and decides to change their tire pressures:
You can change the tire pressure anytime you want, but keep in mind that the whole TPMS system is based on using *cold tire pressures* as the reference point. Plus - all the referenced pressures on the stickers (North American or European) are cold tire pressures. The tire is only considered to be cold if the vehicle has been sitting for more than 12 hours, and has not been driven more than 1 mile following the 12 hour rest.
This means, if you want to change your pressures, and re-adapt the TPMS system, you need to do it in the morning, after the car has sat overnight and the tires (and the monitors inside the tires) have cooled off completely. Don't rely on how warm the tire feels to your hand as a guide, because it is possible for the outside surface of the tire to feel cold after 3 or 4 hours, while at the same time the pressure sensors inside the tires are still quite hot. Hence the need for the 12 hour cool-off period.
Anyway - if you want to change pressures and re-adapt the TPMS to the new pressures, do it after the car has been sitting unused for 12 hours. After you have changed the tire pressures, go to the TPMS screen on the Front Information Display and Control Head, and press the button that says "Store New Pressures" (or words to that effect). You will get an error message on the display between the speedometer and the tachometer (the Y24 display) once you have done this. It is then necessary to go and drive for about 15 minutes - ideally on an expressway - to heat the tires up and allow the system to re-adapt itself. If you drive all day in stop and go traffic, the tires might not get hot enough to allow the TPMS to re-adapt. This is no big problem - it just means you will be looking at a message that says "TMPS system unavailable" or "TMPS system in learning mode" until you go for a 15 minute highway drive.
Michael


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## Phat Cat (Dec 25, 2004)

*Re: (PanEuropean)*

One further note for those thinking of lowering your tire pressure. On my 1st dealer service visit they set my V8 pressure to 44/48 (without telling me) and the car rode like a rock. So, I reset it using my (not so) trusty gauge to what I thought was the 38/40 it had when I first got it from the dealer. As it turned out, I actually set it to 32/34. The car rode more smoothly, but my gas mileage dropped about 15% from the 38/40 setting. I have since returned it to 40/40 and the mileage is back up. YMMV.


_Modified by Phat Cat at 12:45 PM 4-1-2005_


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## nogood911 (Feb 7, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

as far as I know the reason the tire decal changed is because of the TREAD act that was passed after the Ford Explorer tire issues-The change occured on all 2004 MY VW's
Hope this helps
Cain


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (nogood911)*

Hi Cain:
I am pretty sure you are correct. It appears that prior to that 'TREAD' act, the manufacturer was free to present tire pressure recommendations in the way that they saw fit to do so. The new legislation takes that discretion away from the manufacturer, and requires that they present one pressure recommendation only, using the exact sticker design, colour, and placement as shown above.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (nogood911)*

Just a follow-up post here: While doing some research about a different matter, I came across this inflation pressure table in the 2004 Official Phaeton Repair Manual, published by Robert Bentley. It appears that in the process of doing the translation of the manual from the original German language edition, the authors simply carried over the recommendations of the VW engineers for tire pressures, rather than censoring it out and replacing it with the official US Government "TREAD Act' tire pressure recommendations (which can be found on the sticker attached to the driver door B pillar).

*Volkswagen Engineering Recommended Tire Pressures*
(not legal for use in the United States, but will result in a much more comfortable ride if you happen to visit Mexico or Canada sometime)


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Way up at the top of this thread I posted a picture of a ROW (Rest of World) tire pressure sticker for a Phaeton with a W12 engine in it. As you are aware, if you have read the post this far, there are two different sets of tire pressures for each Phaeton: 1) What VW recommends, and 2) What the US Federal Government knows better. Phaetons sold in North America are not allowed to be labeled with the VW engineering recommendations. So, for the benefit of NAR (North American Region)owners, here is the forbidden information:
*VW Recommended Tire Pressures - SWB Phaeton with V8 gasoline engine*








*VW Recommended Tire Pressures - SWB Phaeton with V10 Diesel engine*
_(Not presently sold in North America)_


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

Maybe I missed it somewhere but Fred I'd like to see some pix of that car of yours. I'd like to see both outside and inside.
Clean 'er up and snap some photos.


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

For the benefit of those of you who also own Touaregs, here is a picture of the European tire pressure sticker for Touaregs. As far as I know, the pressures are the same for all Touaregs, but do not take this as fact, it is speculation. Below is a picture of the actual Touareg that had this sticker on it. It came from the factory with that funny rack on the roof and the winch built in to the front bumper.
For the info of those Touareg forum members who may be reading this - please read the whole thread (starting from the top of page 1), before you make any changes, so you understand the reasons between the different pressures recommended in the United States vs. the rest of the world.
*Touareg Tire Pressure Sticker*








*Touareg to which the above sticker was attached*


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## Paldi (Sep 4, 2004)

Gas milage is down 3-5 MPG or I'm driving different. Front underside touched down of a bump today giving a bash to a rubber under car air duct. Guess I'll be adding a few more pounds to the tires after all.











_Modified by Paldi at 8:23 PM 5-25-2005_


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*


_Quote, originally posted by *Paldi* »_Gas milage is down 3-5 MPG or I'm driving different. Front underside touched down of a bump today giving a bash to a rubber under car air duct. Guess I'll be adding a few more pounds to the tires after all.










Fred:
I think your sample size (number of miles travelled) is too small to allow any accurate conclusions to be drawn about the exact effect of tire pressure on fuel mileage. Although it is reasonable to presume that a decrease in tire pressure would be accompanied by a corresponding *fractional *increase in fuel consumption, suggesting that the difference could be 3 to 5 MPG, based on such as small sample, is not sensible. If it were so, then if everyone in the USA increased their tire pressures by 10 PSI, fuel consumption across the country would drop by 10% overnight, thus forcing the price of oil back down to $20 a barrel.
Right?








I don't bother tracking fuel consumption on my car, simply because I use it so little (about 400 miles a month, on average). What I have noticed, as a result of using the ROW (rest of world) pressure recommendations, is that the ride is both quieter and softer. I can't draw any conclusions about the effect of tire pressure on ground clearance, because I have lowered my car to the default ROW ride height (407 mm front, 401 mm back), and that has muddied the waters. But, my guess is that lowering the tire pressure to the ROW specification would have only a tiny (1 or 2 mm, max) effect on ground clearance.
Michael


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## Paldi (Sep 4, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

The ride height at lower air pressure isn't the issue - it's tire deformation where the rubber meets the pothole, so to speak. The tire doesen't adequately support the sudden compression load an so something scrapes or goes "ouch" like a bent wheel rim!
A 30 mile round trip this morning with a 45 mph average speed and some hills (up and down) yielded just under 17 MPG whilst driving normally - not trying to squeeze out every last drop of fuel. Tires were 35 Front, 33 Rear.
Now, I will increase the pressure 10 percent - about 39 pounds front and 36 pounds rear and report back after running the route again a few times.
Some have suggested that fuel economy and tread life drops dramatically once the tire pressure falls below a certain range. I believe that. My tires have some slight feathering at only 10k miles.



_Modified by Paldi at 2:28 PM 6-11-2005_


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*


_Quote, originally posted by *Paldi* »_...Now, I will increase the pressure 10 percent - 38 pounds front and 36 pounds rear and report back after running the two routes again. 

Why not just try the VW recommended pressures?
*V8 Tire Pressure Sticker - Rest of World*


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## Paldi (Sep 4, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*


_Quote »_Why not just try the VW recommended pressures?

Well Michael, that's exactly what I am doing, per your chart!
I thought I'd try the Engineers Recommended values, which are 10% higher in front on the 255 45 18 summer tires. Seems to be a good safe, compromise between half load and full. 











_Modified by Paldi at 12:51 AM 5-26-2005_


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

Just a head's up here - I note that the gas cap flap sticker and the table from the Service Manual only share one tire size in common, and that is the first line on both of them. The next two sets of numbers going down are for different sizes of tires, if you look at the specs carefully.
I don't know what size of tires comes on a NAR V8 Phaeton, so I can't add more than just a caution to read very carefully.
Michael


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## fly4food (Dec 28, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

I have the 255/45 R 18 on mine.


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## dzier (Jun 19, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

I had missng lug caps on delivery, they were replaced, but I seem to lose one every few months anyway. They keep replacing them.
I reduced my tire pressures to 38 front and 36 rear from the dealer set to the sticker on the car. Unless I am missing something here, it is barely noticeable. Perhaps there is a softer thud on tar strips, but I thought it ws going to be more noticeable than it is.
Am I missing something or are we making a bigger deal out of this than warranted?


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (dzier)*

Speaking for myself, I think I even tend to blow this out of proportion but I have never had a TPMS either. I don't think the issue of tire pressures would be discussed this much on the forum if we didn't have the TPMS systems. Which, raises a question: Just today , my Check Tyre Pressure warning came on. I put air in the tires tonight while the tires were hot and in the morning I will release some air to get back down to the correct pressures , but my question is, do the monitors alert us if we have TOO MUCH pressure in our tires? 
It will seem that I will have to add air about every month because I aired them up properly when we were at the GTG exactly one month ago. This makes me check my wife's car and my motorcycle more often now that I am aware of how quick the pressures drop.


----------



## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*


_Quote, originally posted by *Paldi* »_I can say with reasonable certainty that all USA V8 Phaetons and W12's are fitted with 255 45 18 tires upon delivery to our shores. Some dealers have swapped on 19 or even 20 inch wheels with different tires. I have never seen or read about anyone in US with 17 inch wheels.

Hi Fred:
I hate to correct you again, for fear of sounding like I am picking on you, but there are quite a few Phaetons in North America with the 17 inch wheels. These are available as a no-cost option. The advantage that they offer is that they are snow chain compatible.
It is not common for dealers to order Phaetons with the 17 inch wheels, at least, not more than once, anyway







- but, I saw one in the showroom of Queensway Volkswagen in Toronto last month.
Here is a link that will take you to the 2005 Phaeton Specifications List from VW of A. This will open in a new window, as an Adobe Acrobat document.
Michael


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## Paldi (Sep 4, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

The Specifications List is very informative. Thanks for posting it.
I edited my post to reflect the availibility of the "optional" 17 inch wheels. I am very curious to discover what the majority of 2004 Phaeton V8 owners - with the standard 18" Challenge wheels and 255 45 R 18 tires - are running for tire pressure.



_Modified by Paldi at 2:34 PM 6-11-2005_


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

I hate to say this, but I believe I am going to have to raise my suspension back up. I noticed tonight on a very smooth interstate that I travel frequently on that a roaring sound has developed at above 65 mph or so. It was bad enough that even my radio listening was overridden by the roar. I thought, oh no! Is my engine having a problem, but I threw it in neutral and the roar continued without any change. Could it be that I just need to rotate my tires? I almost have 8000 miles on them and usually I rotate tires at 10K miles.. They look fine at a casual observation.


----------



## PhaetonChix (Dec 16, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (dcowan699)*

David, 
Please keep me in the loop. I'm very interested to hear the outcome. According to my friend, the tech from the owners clinic, lowering the car should not cause any issues. I do know the Phaeton I was driving had badly cupped tires by 9K...mind you they were Y-rates and that car was driven like it was stolen; not only by me, but by sales people durning training.
~PC


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PhaetonChix)*

I honestly feel it just needs a rotation because I lowered my car even further (improperly at that) and kept it that way for over 6 weeks and it never made a sound. This was back in early February. I raised it back up after 6 weeks and relowered it at the GTG. I will rotate them next week after my trip to Florida and then see what happens. It was not horrible tonight but just bad enough to get my attention.


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## dcowan699 (Nov 22, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (dcowan699)*

A big thanks to Chris and Phaetonchx for faxing me the worksheet for the 10K mile check up. It INCLUDES the rotation of tires so that means I won't be doing it next week. A rotation of the wheels is due on every 10K mile interval. Today the roar seems to be gone. I may have cried wolf and just thought I heard something unusual because today I never heard it. I must have had a Harley Davidson following me and didn't see it. Still I think the rotation and alignment are in store for my 10K interval. I probably will have to pay out of pocket for the alignment.


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## Paldi (Sep 4, 2004)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

I've been running 39 front, 36 rear for about a week and was unhappy with the front. Just a little too harsh on rough roads - so I dropped it to 36 front this morning.
It appears to be a good setting from the standpoint of ride comfort is. Set the rears depending on your average load. Be sure to increase it if you go to a fully loaded scenario.
I thought the 35 Front and 32 Rear recommended on the ROW gas door sticker for 1/2 load ( 2 occupants and some luggage ) was too light for me and the roads I travel over - although the ride was like butter.
Michael, 
On the discrepancy between the ROW sticker and ROW table, do you know if the difference may be because one (the sticker) is for the SWB cars and the other (the chart) is for the long body cars?



_Modified by Paldi at 2:38 PM 6-11-2005_


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## PanEuropean (Nov 3, 2001)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (Paldi)*


_Quote, originally posted by *Paldi* »_On the discrepancy between the ROW sticker and ROW table, do you know if the difference may be because one (the sticker) is for the SWB cars and the other (the chart) is for the long body cars?

For the V8, that is possible. For the W12 - the European car that was attached to the W12 sticker was a LWB car.
Michael


----------



## Paldi (Sep 4, 2004)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Michael,
Last week I lowered my tire pressures from 39 - 36 to 36 - 36 but today when I checked they read 35 - 35. Each time the reset was performed first thing in the morning after the Phaeton sat parked overnight. Somebody's sneeking into my garage and stealing the rare air of the Phaeton, or...?
Just thought I'd ask if the tire pressure sensors are known for this.


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## PanEuropean (Nov 3, 2001)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (Paldi)*

Hello Fred:
Most likely the change in indicated pressure is the result of a change in ambient air temperature or barometric pressure. The tire pressure sensors themselves are entirely within the pressurized portion of the tire, so it is not possible for them to 'leak', as you suggest.
I think that in general, a pressure difference of one PSI can safely be disregarded - that is close to the limit of gauge accuracy, and you can sometimes see a one PSI difference just as a result of changes in ambient air pressure and ambient air temperature. In other words, nothing inside the tire has changed, the atmosphere around the tire has changed. Keep in mind that tire pressure gauges measure pressure relative to the atmosphere surrounding the tire, not absolute pressure.
Michael


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## Gobuster (May 19, 2005)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

I've had my V8 Phaeton for a few days and am starting to learn more about it daily. I had read this thread and was aware that it might be a good idea to check the pressures and adjust to the European values. 
Well, the ride did seem somewhat harsh, not as smooth as the demo car I drove, and the TPMS was indicating 39F 44R. So, this evening, after the tires had 6 hours to cool, I got out my trusted tire gauge, which I know is accurate to +/- 1 psi, and checked the pressures. They were all even - at 56 psi! I was shocked when the gauge needle flew around almost to the stop at 60 psi!! It took time to let the air out to 38F 37R. Needless to say, the ride is much improved and I'm even happier with the car! Tomorrow I'll reprogram the TPMS, which now indicates a flat tire! 
Rob


----------



## PanEuropean (Nov 3, 2001)

*Re: V8 Tire Pressures, Ride Comfort and Road Noise (Gobuster)*

Hi Rob:
Wow - 56 is a bit too high, I think that is more than the tire manufacturer allows.
Keep in mind that the tires need to 'warm up' (from stone cold) to complete the TPMS learning process. This normally requires about 5 to 10 miles of freeway driving. When you initiate the learning process, you will see a message in the display between the speedometer and tachometer indicating that the learning process has started. This disappears after a few moments, and then you will see an orange icon showing a tire with a line through it. This icon will remain until the learning process is complete.
If you wish, you can also watch the process by pressing the VEHICLE button on the infotainment screen. While the TPMS is learning new pressures, no numbers will be displayed beside the tires. When the process is complete, numbers will appear. It is normal for the numbers that appear on the screen to be different from the pressure you have set (with a calibrated gauge) by up to 2 pounds. Don't worry about that, it has to do with issues of absolute vs. relative pressure. If you set (for example) 43 front and 39 rear, and when the learning process is finished, the display indicates 44 front and 40 rear - that's fine.
If you end your 'learning process drive' before the learning process has completed, then you have to wait until everything cools down (in practice, this means wait until the next morning) to start it all over again.
When I went out to my car today, I was a bit surprised to see a TPMS warning that said "check pressures". I checked, and everything was fine as far as I could tell - all the pressures were within 1 PSI of what I had set them at several months ago. But, today was the first really hot day in the region that I live in, so perhaps the big change in temperature caused the TPMS system to think something was not correct. I just put the system through another learning cycle after I checked to make sure all the pressures were OK. The car completed that without problems, and all is back to normal now.
Michael


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## Gobuster (May 19, 2005)

Michael,
Thanks for the tip on TPMS reprogramming, the manual fails to describe the complete process in detail. In general, the manual is poor, failing to adequately explain many processes. You, on the other hand, do a great job. Thanks.
Rob


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## PanEuropean (Nov 3, 2001)

*Re: (Gobuster)*

Hi Folks:
I have an important error correction to make here. I have just found out that photo of the European W12 tire pressure sticker on the first page of this thread is a picture of a Short Wheelbase W12 tire sticker, not a Long Wheelbase one. All of the North American Phaetons are Long Wheelbase models.
Below is a picture of a European W12 *Long Wheelbase* tire sticker. In light of this new information, I think it is probably important for safety reasons that we reconsider the pressures that we are running in our W12 Phaetons. For sure, I will be switching over to the higher pressures that are indicated in the sticker below.
Michael
*European W12 Long Wheelbase Tire Sticker*


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## stjarna (Aug 18, 2005)

*Re: (PanEuropean)*

This is exactly the pressure setting that my dealer always resets my tires to each time I take it in. I had thought that they sure were putting it high versus what you guys had been talking about, but now it sounds like the dealer (Park Cities VW in Dallas) was doing it right all along.
http://****************.com/smile/emthup.gif


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## dtwphaeton (Sep 7, 2004)

*Re: (PanEuropean)*

Michael, this is great information, which I will start following. The tire experts I know always strongly recommend higher pressures than placarded here in the States. Why do you think the recommended NA pressures are lower? Speed limits? Comfort?


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## PanEuropean (Nov 3, 2001)

*Re: (dtwphaeton)*


_Quote, originally posted by *dtwphaeton* »_ Why do you think the recommended NA pressures are lower? Speed limits? Comfort?

Neither. The difference is so small (1 PSI) that it is probably just due to rounding the numbers off when they are converted from the original specifications, which are in BAR, not PSI.
Michael


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## geowben (Jan 26, 2005)

Michael, what pressures are you going to run in your W12? If I read this correctly, it should be 44 in both front and rear? thanks for the info.


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## W126C (Jan 27, 2005)

*Re: (geowben)*

I am redirecting the tire pressure discussion back to this thread. 
I have never got a straight answer to what pressures are correct for the W12 with 19" wheels. I've posted before that, 41 psi. front and 39 psi. rear has worked for me. This is not a full load figure, ie, one to two people in the car without luggage. Just what has worked for me. For a long trip with four people and luggage, I would change the pressures. Maybe to 43 psi. front and 45 psi. rear.
Anyway, I took my car in for the 30K service and when I got the car back my tire pressures had been changed. The tech reset them to 41 psi. front and 48 psi. rear. This was after a balance, rotate and alignment check. BTW, the alignment was still right on, no change. I love that part. http://****************.com/smile/emthup.gif So what I plan to do is to put it back to the 41 psi.F/39 psi.R. 
So my question is where did the service tech come up with the pressures? I will be calling him tomorrow to ask, kindly.
I think Fred is running the same psi.,(41/39 psi.) with his 19" wheels. 
Regards,
Brent


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## Paldi (Sep 4, 2004)

*Re: (W126C)*


_Quote, originally posted by *W126C* »_
I think Fred is running the same psi.,(41/39 psi.) with his 19" wheels. 


I'm close - it depends on ambient temp when I do the "learn" but I think my spread is about 4 pounds between front and rear = 42-38 or when colder = 40-36. Mine's a V8.


_Modified by Paldi at 10:59 PM 5-3-2006_


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## W126C (Jan 27, 2005)

*Re: (Paldi)*

Fred,
So how is the wear? Even?
Leaving the dealer I felt the ride was a little "bumpy." I am assuming it was coming from the rear. Not bad, just not the same. I guess I should have picked up a few hitch hikers.







I'll change it back this weekend. I'm sure all will be fine.
Regards,
Brent


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## Paldi (Sep 4, 2004)

*Re: (W126C)*


_Quote, originally posted by *W126C* »_Fred,
So how is the wear? Even?


It's hard to say as I've been all over the place with pressure. The fronts have some wear in the shoulders of grooves on the outer edge of the tread just before it wraps over onto the sidewall. As if, perhaps the small pebbles that slip in and out of there have teeth? It's only the front tire that have this slight wear.
But I also think I was under-inflated for 3-5,000 miles when I was running only 35 pounds in the fronts. Get down on your hands and knees and look at the "flat" spot where the tire meets the road and see how the sidwalls and the tread that shows look. Are you running with that area of sidewall on the street or is the tire inflated enough to bring it off the street? Then look at the rears. 
It seems to me the tire contact "patch" should be about the same front and rear. Very unscientific, I know.) Anyway, after 10,000 miles I will rotate front to rear. (In 3k more miles to go.)


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## Eyecare (Apr 20, 2006)

For new Phaeton (or new tire) owners don't forget that you'll need a hundred miles or so to "break in" you tires. Here's a good reference on tires: Tire Tech


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## Hamersly (Feb 28, 2007)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

I just bought a 2004 W12 earlier this week, and like many others have found the information in this forum invaluable. Thanks to everyone, especially Michael. A couple of North American W12 owners have said they run the 38f/35r half-load tire pressures recommended by the VW engineers. But if I'm correct in thinking all the NA W12's have the long wheel base, shouldn't the half-load pressure be 45f/44r?


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## chrisj428 (Feb 26, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Hamersly)*

Bill,
Warmest welcomes to the Phaeton Forum.
As you've undoubtedly come to realize, you're driving a very special vehicle -- one that enjoys a passionate following rarely seen in a "mass-market" vehicle.
As for the tire pressures, I run 38F/35R, however that is in my V8. I would think a slightly higher pressure would be warranted for the heavier engine and the warmer temperatures in your neck of the woods.


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## car_guy (Aug 19, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (chrisj428)*


_Quote, originally posted by *chrisj428* »_Bill,
Warmest welcomes to the Phaeton Forum.
As you've undoubtedly come to realize, you're driving a very special vehicle -- one that enjoys a passionate following rarely seen in a "mass-market" vehicle.
As for the tire pressures, I run 38F/35R, however that is in my V8. I would think a slightly higher pressure would be warranted for the heavier engine and the warmer temperatures in your neck of the woods. 

I know we've been through this a few hundred times, but is 38F/35R VW's recommendation for the V8? I run higher pressures because I thought they were required and I like to lower them to soften the ride a bit if it were OK.
And a question. What role does a warmer temperature play in setting the pressures?


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## chrisj428 (Feb 26, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (car_guy)*


_Quote, originally posted by *car_guy* »_I know we've been through this a few hundred times, but is 38F/35R VW's recommendation for the V8? I run higher pressures because I thought they were required and I like to lower them to soften the ride a bit if it were OK.

No worries -- it's a bit confusing. Here's what I found:

_Quote, originally posted by *PanEuropean* »_*Volkswagen Engineering Recommended Tire Pressures*
(not legal for use in the United States, but will result in a much more comfortable ride if you happen to visit Mexico or Canada sometime)



_Quote, originally posted by *car_guy* »_And a question. What role does a warmer temperature play in setting the pressures?

Tire failure, i.e.: blowouts, result from the tire overheating and the tire layers delaminating. There are three components involved in tire temperatures: speed, load and inflation. The higher the speed, the higher the temperatures -- hence the speed rated tires. Load plays a role as well, which is why Phaetons (especially the "heavies") require the 103 load rating. Finally, inflation.
If you remember the Firestone/Ford debacle, a common thread was all three of these limits were exceeded -- the tires were typically underinflated, overloaded and it was hot outside (obviously a tire can overheat in a Minnesota winter, but it's less of a possibility than a Dallas summer).
VW originally had an inflation matrix showing four quadrants: 1/2 load, under 100mph; 1/2 load, over 100mph; full load, under 100 mph; full load, over 100 mph. Unfortunately, most in the USA can't be bothered to check their tires' pressures in the first place, let alone adjust them to the conditions they're going to face. So was born TREAD and the only "legal" inflation pressures listed are the "full load, over 100 mph" numbers, since those offer the largest margin of safety, albeit at a huge detriment to ride comfort.


_Modified by PanEuropean at 3:48 AM 2-22-2008_


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## bobschneider (Oct 12, 2004)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (chrisj428)*

Chris, are the W12 pressures in that chart for the LWB models, or the Europe only SWB ones?


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## chrisj428 (Feb 26, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (bobschneider)*


_Quote, originally posted by *bobschneider* »_Chris, are the W12 pressures in that chart for the LWB models, or the Europe only SWB ones?

These are the W12 LWB ones (note: you should only use the "bottom two" with the 103Y rating for the 45-series tires as these are the ones fitted to the NAR W12 vehicles):

_Quote, originally posted by *PanEuropean* »_*European W12 Long Wheelbase Tire Sticker*










_Modified by chrisj428 at 4:33 PM 3-9-2007_


_Modified by PanEuropean at 3:49 AM 2-22-2008_


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## car_guy (Aug 19, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (chrisj428)*

Chris, this is very useful, as I can now justify lowering the pressures. I currently run 41 front and rear on my 235/55-17 snow tires.
Do you know how many pounds constitutes half load and full load? 
I must say that the recommended rear tire pressure difference between half load (33 lb.) and full load (45 lb.) seems extreme. Say my car weighs 5600 lb. (5200 + 400) half loaded and the difference between half and full load is 400 lb. The recommended tire pressure increase is 36% while the weight of the car has only increased 7%. I'm not expecting a linear relationship, but...
But who am I to argue with engineers?


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (car_guy)*


_Quote, originally posted by *car_guy* »_Do you know how many pounds constitutes half load and full load? 

Steven:
I presume your question is directed to the V8 LWB. When I get back to Switzerland next week, I'll order a tire pressure sticker (gas flap sticker) for a LWB V8 and that will give us the answer. The tire pressure sticker for a LWB W12 is shown above.
Michael


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## Spectral (Dec 21, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

Looking at the charts above, it appears that a tire with a load rating as low as 99 would be acceptable on a V8 Phaeton?? I am looking at some tires that have a 100 load rating.


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## car_guy (Aug 19, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Spectral)*


_Quote, originally posted by *Spectral* »_Looking at the charts above, it appears that a tire with a load rating as low as 99 would be acceptable on a V8 Phaeton?? I am looking at some tires that have a 100 load rating.

Don't forget to take the 5200 lb. curb weight of the car and add maximum carrying capacity (is my guess of 1100lb. close?) and then multiply that total by the 55 percent carried by the front wheels, and then divide by two. That should give you the maximum weight that the tire must carry.
So that comes to 1733 lb. 99 Load rating is for 1709 lb. 100 Load rating is for 1764 lb.
So the 100s technically would do it, while the 99's don't. Is this cutting it too close for safety?
And this contradicts the chart that Chris has displayed earlier. 


_Modified by car_guy at 7:41 PM 3-12-2007_


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (Spectral)*


_Quote, originally posted by *Spectral* »_Looking at the charts above, it appears that a tire with a load rating as low as 99 would be acceptable on a V8 Phaeton?

I don't know the answer to that beyond what is shown above. I do know that the required load rating varies depending on the diameter and the aspect ratio of the tire... which more or less means you have to play it by the charts.
Michael


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## Spectral (Dec 21, 2005)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (car_guy)*


_Quote, originally posted by *car_guy* »_
So that comes to 1733 lb. 99 Load rating is for 1709 lb. 100 Load rating is for 1764 lb. So the 100s technically would do it, while the 99's don't. Is this cutting it too close for safety?
And this contradicts the chart that Chris has displayed earlier. 

_Modified by car_guy at 7:41 PM 3-12-2007_


Thanks for doing the math. I use the Phaeton primarily for business and typically travel alone. The 100 load rating sounds safe enough for me.


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## vah (Oct 12, 2007)

*tire pressure on good year f1 all season*

the setting on my original tires were 39 and 45.
i just gotten the good year f1 (255/45/r18)
the dealer (tire) set it up to 34 and 35.
Chris recommend that i set it to 40 and 38. (i trust him more then any dealer).
but i am just wonder, what are others with this tire, did?
than you.


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## Jack Orr (Mar 15, 2000)

*Re: tire pressure on good year f1 all season (vah)*

My dealer set my new Serenities at 35.


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## CLMims (Jul 13, 2007)

*Re: tire pressure on good year f1 all season (Jack Orr)*

I went with the car's specs and have my Goodyear F1's set to 45 rear and 39 front, although when I had the TPMS adapted they must have been a tad warm (it shows 47/42)...




_Modified by CLMims at 5:38 PM 2-18-2008_


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## mlong1 (Dec 6, 2007)

*Re: tire pressure on good year f1 all season (CLMims)*

I have the F1 tires on mine- 45, 39.
TPMS module is being replaced this week though, but that is another story.


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## vah (Oct 12, 2007)

*Re: tire pressure on good year f1 all season (mlong1)*

i called good-year hot line.
they told me that i should follow the manufacture spec, and not what their installer talk me.


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## PanEuropean (Nov 3, 2001)

*Re: tire pressure on good year f1 all season (vah)*

I agree with that.
The pressures that are shown on the door-sticker (on the B pillar, which is to your right when you open the driver door) are what is appropriate for your car with a full load. These are the pressures I use for the tires on my W12 and I am very happy with the results.
Be aware that if you use significantly lower pressures (anything down in the 30s), you might have troubles with the TPMS (Tire Pressure Monitoring System). There is a 'hard floor' for minimum tire pressure programmed into the TPMS - I am not sure exactly what it is, but I suspect it is probably about 10 PSI less than recommended pressures - this being a rough guess.
The best tire wear will be achieved when manufacturer's recommended pressures are set.
Michael


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## PanEuropean (Nov 3, 2001)

*Re: tire pressure on good year f1 all season (PanEuropean)*

Photos re-hosted, new discussion merged onto the end of the original discussion.
For those of you who have not seen this thread before, it is interesting, you might want to go to page 1 and follow it all the way through. It evolves, so don't take anything for granted until you have read the whole discussion (3 pages).
Michael


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## Traveller (Jan 6, 2006)

*Tire Pressure*

What type of tires are you running? What tire pressure do you generally keep them at?


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## CLMims (Jul 13, 2007)

*Re: Tire Pressure (Traveller)*

I had to post a response to this after re-reading: 
Since my TPMS was fussing at me anyway for the right front tire being too low, I took the opportunity to try the "half load" settings on my V8; I changed the original pressures from 39 front/45 rear to 38 front/33 rear (although when the TPMS got the new readings it had warmed up to 39/35). 
I could not believe the difference!








When I originally bought the Goodyear F1's, I did so mainly because of the high load rating (109) and high wear rate; it always seemed to ride a bit rough to me, and when I expressed concern to the dealer, they told me it was due to the Z-rated tires. Now, however, the ride has smoothed out considerably: 
+ the seams in the pavement do not jar me 
+ grooved pavement can be heard but not felt
+ my arms are not as sore when I arrive at work/home (I drive 75 miles each way)
The only downside I can tell thus far is a slightly more noticable road noise; I can't tell yet if the gas mileage has changed any, but after filling up this morning I was at 20.1mpg when I got to work (70-80 highway speeds plus DC rush hour speeds)


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## jeffe51 (Aug 8, 2008)

*Tire Pressures*

Just saw the posting regarding weight distribution (front-rear).
Having just installed 4 new tires yesterday, wondering if I'm running the correct tire pressures.
I currently run 39 front and 43 rear.
99% of the time it's not loaded...just me driving or me & front passenger.
Any comments?


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## Prince Ludwig (Mar 24, 2007)

I think you might have misinterpreted the diagram behind the fuel filler cap - because the car is heavier at the front, the tyre pressures should be higher (unless you're carrying passengers and stuff in the boot in which case all the tyres should have high pressures).
Harry


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## Chuckdoc (Jul 25, 2008)

*Re: (Prince Ludwig)*

I was wondering this also. My interior door sticker says 39 front 45 rear. So far its doing okay, but I still get flat tire warnings within a minute of my morning drive....

Chuck


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## Prince Ludwig (Mar 24, 2007)

Unfortunately, the diagram of the car is pretty poor (the difference between the front and back is very minimal) but I assumed that when the car is empty there would be more weight on the front wheels (hence they'd need to have a higher pressure) and when the car was full there would be a more even weight distribuition (all wheels filled to a similar pressure)
Harry


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## remrem (Jan 20, 2008)

*Re: Tire Pressures (jeffe51)*

I suggest you read through this entire thread:
http://forums.vwvortex.com/zerothread?id=1810686
Even though its title refers to the W12, it actually discusses the V8, as well. It also talks about ROW vs. NAR recommendations, as well as short and long wheelbases, so read carefully.
You will learn all about this subject, and will probably still be as unsure as I am as to what pressures to use








Seriously, it may take a bit of experimentation until you find the sweet spot for your particular situation, but at least you will know within what range you should safely limit your experiment.


_Modified by remrem at 12:02 PM 8-22-2008_


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## mhoepfin (Dec 20, 2007)

I found my NAR V8 rides and handles much better at the recommended 39 front and 45 rear.
The only issue I have is the TPMS gives a warning on every wheel when the difference between the front and back tires is more than about 7psi, so it doesn't leave much room for error on keeping your tires inflated.


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## remrem (Jan 20, 2008)

*Re: (mhoepfin)*

I'm running my NAR W12 (with Yokohama Advan Sports 255/45/18) at 42 psi both front and rear.
I've experimented with various combinations from as low as 38 to as high as 48, but I'm pretty happy with the way the car rides at the current settings, except on those rare occasions when I have 4 people in the car and/or a lot of weight in the trunk. Then it becomes a little sluggish and I wish I had a bit more in the rears. But, since I'm running with nitrogen, it's a real pain to find a pumping station just to add a few pounds for those occasions.


_Modified by remrem at 10:04 PM 8-24-2008_


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## ron kramer (Apr 16, 2007)

Phaeton customer care and two dealers have all given me DIFFERENT values to put in. To this day I still do not know what is correct.


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## PanEuropean (Nov 3, 2001)

*Re: (ron kramer)*

If you ever travel with a full load (four passengers), inflate the tires to the pressure indicated on the driver door B pillar sticker. This bright yellow sticker, which is required by American law and is the same design on all cars, can be found just to your right when you open the driver door.
If you never travel with more than two passengers, you can use the slightly lower pressures that are indicated in the VW publications pictured above.
Remember that tire pressures are always determined by the *AUTOMOBILE MANUFACTURER*, not by the tire manufacturer. The automobile manufacturer knows what the vehicle weight is and what the weight distribution is. The tire manufacturer has no idea at all. The only figure that the tire manufacturer ever provides is a maximum inflation pressure (and, of course, a load rating).
Michael


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## brosen (Jun 21, 2009)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (PanEuropean)*

I just installed 5 brand new tires Continental ContactExtreme DWS 255/45 ZR 18 109Y All Season. The Dealer inflated the tires to *39 Front and Spare and 36 Rear*.
Most of the time I am the only passenger in the car (daily commute to work) and sometimes during the weekend the whole family while we go out for lunch (2 adults in the front 2 teenagers in the rear).
With my previous set of tires Kumho 255/45 ZR 18 99Y All Season the dealer inflated the tires to *44 all 5 of them*. 
Right now I am confused







I do not really know what should be the right pressure, please advice, thanks


_Modified by brosen at 8:43 AM 8-10-2009_


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## PanEuropean (Nov 3, 2001)

*Re: W12 Tire Pressures, Ride Comfort and Road Noise (brosen)*

Bernard:
This thread is entitled "*W12* Tire Pressures". You have a V8. The vehicles are very different.
To determine the correct inflation pressure for your tires, refer either to the sticker on the driver door B pillar (the pillar between the front and rear doors on the driver side), or to the tire inflation information in your owner manual.
Michael


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## 30mpg (Mar 30, 2008)

*pressures for summer tires vs. snow tires*

I'm glad I just read this whole thread and wish I would have done so two years ago. I've been running my Bridgestone Turenza Serenitys at full pressure and always thought the ride was a little harsh when it's just me.

My question is about snow tires. All the diagrams and specs seem to talk about Summer tires. I just got a new set of Blizzak LM-22's for my Phaeton (255/45-18) and am curious if/how the manufacturer recommended pressures differ for snow tires vs. summer tires?

Thank you!!!

cheers,
Albert


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## PanEuropean (Nov 3, 2001)

Hello Albert:

To the best of my knowledge, the pressures used for winter tires (appropriate to vehicle load) are the same as the pressures used for summer tires. I believe that the key issue is the tire size, not the tread pattern.

Michael


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## PanEuropean (Nov 3, 2001)

Photos re-hosted.

Michael


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