# 285/50/18 Tires



## Bigtop (Jan 8, 2004)

Time for new tires on my 18 inch rims.
Has anyone fitted 285/50/18 size? Section width is about 11.7" so they shoul fit on the V8. 
I see on tirerack.com there are 4 choices:
Dunlop SP Sport 9000 
Bridgestone Dueler H/P Sport
Continental CrossContact UHP
Michelin 4x4 Diamaris
Yokohama ADVAN S.T.
Yokohama AVS S/T
Pirelli Scorpion Zero Asimmetrico
Any feedback would be much appreciated.


----------



## jrtouareg (Jun 15, 2005)

*Re: 285/50/18 Tires (Bigtop)*

I put 275/55/18 TOYO ST Proxes. Really made the car look a lot better. The tire place I went to did not recommend that width(285) tire for the stock rims.


----------



## Bigtop (Jan 8, 2004)

I am told that if you go 285/50 that the width is almost identical to 275/55. If you put 285/55 size on, you are risking the width becoming too large.


----------



## jinxegg (Oct 14, 2004)

*Re: (Bigtop)*


_Quote, originally posted by *Bigtop* »_I am told that if you go 285/50 that the width is almost identical to 275/55. If you put 285/55 size on, you are risking the width becoming too large.

The width is the same for both 285/50 and 285/55: 285 cm.
Moreover, there is a significant difference in overall diameter between 275/55 and 285/50 i.e.285/50 is 18mm (0.78 inch) smaller than the stock 275/55.
in this case you're gonna have wrong speedo reading and bigger fuel consumption.


----------



## Bigtop (Jan 8, 2004)

Just because is indicates 285 mm does not mean that it will be exactly that width. They vary by manufacturer.
The OEM Contintal Contacts 255/55/18 have an overall diameter of 29" and a width of 10.". The Continental UHP 285/50/18 have and overall diameter of 29.3" and a width of 11.7". The Yokohama Advan ST are almost identical in the same size at Overall Diameter 29.2" and 11.6" width.
The difference in diameter is very negligable with regards to speedo readings and fuel efficiency. However, you get a better width of tire.


----------



## Bigtop (Jan 8, 2004)

Just looked at the Toyo Proxy ST's in the 275/55/18 size. The overall diameter is 29.8". Which is a larger OD than the OEM tires. So, from what I am researching is you can go with a wider (width) tire in the 285/50 size but not really increase the overall diameter that much, but get a fatter width tire. I think the max width the V* will allow is 11.9", someone correct me if I am wrong on that.


----------



## Bigtop (Jan 8, 2004)

I meant V8.


----------



## Caribmon71 (Apr 22, 2005)

I just installed a 285/45 on my V8 (today). I laid the 275/45 next to the 285/45. There was a difference in width of about 10mm, which should be about dead on. The 285 was obviously wider than the 275.
The aspect ratio (the number after the slash) has absolutely nothing to do with the width of the tire. It gives you the height of the sidewall when calculated mathematically.
275mm x 55 (aspect ratio) = 151.25mm sidewall
285mm X 50 (aspect ratio) = 142.50mm sidewall
The sidewall of the 275/55 is 8.75mm taller than the sidewall of the 285/50 tire. When stood side by side, and since there is sidewall on top of the rim and under the rim, the 275/55 tire will be 17.5mm taller than the 285/50 tire. Width will be the same on both tires.


----------



## Caribmon71 (Apr 22, 2005)

The 285/55 18 tire you are talking about should yield about a 30.34" outside diameter. The setup I installed today (285/45 19) should have yielded a 29.1" outside diameter.
The setup you're talking about is about 1.25" larger than mine and 1.6" larger than OEM outside diameter. You may encounter a rub issue when turning the wheels. The rear won't be a problem.
Width wise only, 285mm is ok. However, if your sidewall is too tall, your tires may rub when you turn the wheel.
I really wanted to install a 295/45 19, but my factory Atheos are only 9" wide. The 295mm tire requires at least a 9.5" wide rim. That tire would have had an outside diameter of 29.45" I'm guessing that it would have fit.
Anyone have this tire size?


----------



## jinxegg (Oct 14, 2004)

*Re: (Bigtop)*



Bigtop said:


> Just because is indicates 285 mm does not mean that it will be exactly that width. They vary by manufacturer.....
> QUOTE]
> It is always exactly that width for every make of tire in every part of the globe.
> As for the diameter issue, you 're right. Instead of the 255/55, I was comparing 275/55 to 285/50.


----------



## jrtouareg (Jun 15, 2005)

There is a maximum recommended width you can install on the stock rims. The stock rims are only 8" wide. According to Tire Rack, 285 width tire should be mounted on 9" rims, it will fit on 8" rims, but tire contact patch will be reduced affecting performance.


----------



## Bigtop (Jan 8, 2004)

The OE Continental Contact 4x4 255/55/188 have a section width of 10.4" with an overall diameter of 29."
Putting a 275/55/18 tire on that tirerack recommended does not make sense, because the section width is 10.7" and the overall diameter 30.4".
So for a measly extra .2" in width, you gain a whole 1.4" in overall diameter. That is not beneficial to handling or the desire to have a wider tire on an 18" rim.
If you put a 285/55/18 tire on, the section width is 11.7" and the overall diameter is 29.2". Which means you gain 1.7" in tire width but only increase the overall diameter by .2" Way better for handling.
The statement that says that if you put a 285/50/18 tire on an 8" rim reduces handling because the tire contact patch is reduced does not make real sense either. The upsizing will have a positive gain in contact patch overall rather than a reduction. Let's say the tire does pull up a little because of the 8" rim, it will not pull up over an inch in contact patch diameter, maybe 1/2 to 1/2", which means you still have a gain. Plus the overall diameter is almost idential to the OE tire. The larger the overall diameter the reduction in handling. So in my opinion, putting a 285/50/18 tire will be better than the 275/55/18 tire, remembering that the VW max recommendation in OE rim tire width is 11.9"


----------



## Caribmon71 (Apr 22, 2005)

A 285/55 18 tire is 11.22" wide, not 11.7" - and has an outside diameter of 30.34". 
The 275/55 18 tire is 10.83" wide with an outside diameter of 29.91".
The OE 255/55 18 you're talking about is 10.04" wide and has an outside diameter of 29.04.
The 285/50 18 is 11.22" wide and has an outside diameter of 29.22".
I didn't think you could safely mount a 285mm wide tire on an 8" wide rim. If so, then despite the tire manufacturer's recomendation, I could have mounted a 295mm wide tire (which is what I really wanted) to a 9" wide rim.
Where are you getting your numbers from? They seem to be off some.


----------



## jinxegg (Oct 14, 2004)

*Re: (Bigtop)*

Bigtop, get your numbers right.


----------



## Bigtop (Jan 8, 2004)

I am getting the figures from tirerack. Choose one of the tires you are interested in and hit the Specifications tab.


----------



## jrtouareg (Jun 15, 2005)

*Re: (Bigtop)*

I struggled with this on my 04 V8. I finally settled on 275/55/18 and was glad I did. Caribmon71's numbers are correct and that is what I calculated when I was sizing up my tires.


----------



## henna gaijin (Jun 30, 2005)

*Re: 18" Tires*

Man, this thread is painful to read








In choosing a tire, there are many factors to consider and in th end it is a highly personal choice. Basically, if it makes you happy, you made the right choice.
However, there are some good reasons for choosing one tire size over another.
From Bigtop's posts, I will assume he is looking for a new tire to mount on stock 18" wheels and that these tires will be used primarily onroad and with a "performance" driving style (hence the desire for a wider tire).
Some points to consider in tire choice:
1. Unsprung weight - basically everything not supported by the car's suspension. In this case, we are talking about wheels and tires. Since the stock 18" wheels are a given, then we can focus just on the tires. In any case, lighter is better. The more unsprung weight, the less performance.
2. Overall tire diameter - from a lot of searching, I have found that VW/Porsche recommend tires for the Touareg/Cayenne in the diameter range of 28.7" - 29.5". Smaller is NG and larger is NG. There are many reasons for this: mileage, performance, suspension geometry, compatibility with the onboard spare tire, etc., etc.
3. OEM tire specs - as much as we all may dislike the OEM tires, they were chosen to meet a set of specifications that were in concert with design criteria of the Touareg. Deviation from any of these specs could adversely affect performance and/or safety.
With these points in mind, let's look at some of the tires and tire size choices discussed above:
OEM tire:
Continental 4x4 Contact 255/55VR18 109V XL
Max. inflation pressure: 51psi
Max. load: 2271#
Tire weight: 32#
Section width: 10.4"
Overall diameter: 29"
Comments: OEM - meets all specs and performance criteria
275/55-18 tire:
Michelin Cross-Terrain SUV 275/55SR18 109S SL
Max. inflation pressure: 35psi
Max. load: 2271#
Tire weight: 36#
Section width: 10.5"
Overall diameter: 30.1"
Comments: Lower speed rating - not suitable for speeds above 112 mph, max. inflation pressure of 35psi does not meet the requirements of 38-46psi for 18" tires depending on load, tire weight is 4# more than OEM tire and overall diameter is 0.6" larger than allowed maximum. NOT AN ACCEPTABLE REPLACEMENT TIRE.
285/55-18 tire:
Yokohama AVS S/T 285/55VR18 113V SL
Max. inflation pressure: 44psi
Max. load: 2535#
Tire weight: 45#
Section width: 11.7"
Overall diameter: 30.4"
Comments: Max. inflation pressure is too low, tire weighs 13# more than OEM tire and overall diameter is too large. NOT AN ACCEPTABLE REPLACEMENT TIRE.
285/50-18 tire:
Bridgestone Dueler H/P Sport 285/50WR18 109W SL
Max. inflation pressure: 51psi
Max. load: 2271#
Tire weight: 42#
Section width: 11.7" (on 9" wheel)
Overall diameter: 29.3"
Comments: Tire weighs 10# more than OEM tire. See summary below for further comments.
Summary:
If you want a wider tire than the OEM 18" tires, it is probably better to go to a larger (or smaller) wheel than to try to force fit a wide tire onto the 18" wheels. Of the alternative sizes discussed here, only the 285/50-18 looks like it could be "force fit," but at 10# of additional weight per tire, it would probably perform less well in real world driving than the OEM 255/55-18 tire.
Certainly there are a lot of different tire/wheel combos out there - to each his own. But if you really want performance with the 18" wheels, my recommendation would be a good performance tire in the stock 255/55-18 size.
Hope tis clears up some of the confusion (unless I screwed up some numbers







)
ETA:
My original post was based on tires available from the TireRack.
I can add the following tire as a possible substitute for the OEM size:
Toyo Proxes S/T 275/55VR18 114V
Max. inflation pressure: 50psi
Max. load: 2601#
Tire weight: 39#
Section width: 11.1" (on 8.5" wheels)
Overall diameter: 29.8"
Comments: Although slightly larger than recommended diameter, this should not be a problem. However, the additional 7# of tire weight may or may not be an issue depending on how hard you drive and what level of performance you expect.
In any event, the Toyo Proxes S/T in 275/55VR18 would be a much better choice than any 285/50-18 tire.



_Modified by henna gaijin at 1:36 PM 5-11-2006_


----------



## jrtouareg (Jun 15, 2005)

Toyo Proxes St - 275/55/18, v rated, m+s rated, 420 treadwear rating, 114 load rating, 50 psi max. pressure, A-traction, A-temperature. I'm on my 4th T-reg and have replaced several sets of tires. This has been the best replacement tire I've had. My 3rd t-Reg had 26,000 mileson this tire and showed little wear.


----------



## Widman (Feb 25, 2004)

*Re: 285/50/18 Tires (Bigtop)*

I would suggest staying away from the Yokohama Advan ST. I have the 285-14-19s on my egg and while a great handling and traction tire, after 7K miles they are cupping and I get a low speed noise and vibration to the point that at 8K I am replacing them with either the Toyo Proxes ST or Michelin Latitude Touring HP.


----------



## Tregger (Mar 9, 2004)

I would agree. While I was noticing more noise with 26K on my Toyo's in the 285 size there was a still a ton of tread left.


----------



## henna gaijin (Jun 30, 2005)

*Re: (jrtouareg)*


_Quote, originally posted by *jrtouareg* »_Toyo Proxes St - 275/55/18, v rated, m+s rated, 420 treadwear rating, 114 load rating, 50 psi max. pressure, A-traction, A-temperature. I'm on my 4th T-reg and have replaced several sets of tires. This has been the best replacement tire I've had. My 3rd t-Reg had 26,000 mileson this tire and showed little wear.

I agree. See my edited post above to add the Toyo Proxes S/T.


----------



## Bigtop (Jan 8, 2004)

Very interesting. How about the Continental CrossContact UHP's 285/50/18. They have a 51psi inflation, weigh 38lbs, Rim Width range 8-10", Section Width 11.7", Overall Diameter 29.3" (data from Tirerack).
It seems they are almost made to fit the 18" rims, same manufacturer as my old OEM tires, almost the same spec except the weight is a little heavier and they are fatter (wider), which is what I was after.
Personally, I loved the handling of the Contact 4x4 tires, even though they did not last that long. For performance I don't really mind sacrificing longevity.
So I think I am going to buy them unless someone tells me I am making a mistake!!!


----------



## henna gaijin (Jun 30, 2005)

*Re: (Bigtop)*


_Quote, originally posted by *Bigtop* »_So I think I am going to buy them unless someone tells me I am making a mistake!!!

Be sure to post pics and let us know how you like them


----------



## Caribmon71 (Apr 22, 2005)

I think that is a good tire choice. In fact, it is the tire I was after, but it is not yet available in the size I require. My only concern would be the width of the tire fitting on an 8" rim (is that the correct rim width?). But if you know for sure that it will be ok, then go for it! Good luck and let us know. http://****************.com/smile/emthup.gif 


_Modified by Caribmon71 at 1:13 PM 5-12-2006_


----------



## Caribmon71 (Apr 22, 2005)

*Re: (jrtouareg)*

Here in Puerto Rico, we just replace the tires when they wear down; not the entire vehicle. Seems like you're tossing the entire vehicle out with the tires. Man that's gotta be nice







http://****************.com/smile/emthup.gif .


----------



## Bigtop (Jan 8, 2004)

O.K I did it. Got the Contintal Cross Contact UHP 285/50/18 put on this afternoon. I haven't had a chance to really test them yet. However, they totally look the dogs bollocks. There is absolutely no problem with clearance on full lock or with the wheel arches or the strut. All fits O.K. Driving home they seemed to be very quiet and smooth running. I will whack them around some corners and see how they drift or start to break and let you know.
I do have one concern though. I bought them from tirerack.com on Saturday, they arrived at my local tire dealer on Wednesday (today- that is great service!). The chap at the local tire dealership said I was nuts to have the tire pressures at 42psi on the rears and 38 psi on the front. He has filled them to 35psi all around. I made him change the pressures according to VW for the 18" rims and nearest tire size 255/55/18 spec. He said that they will just wear out abnormally and I am totally wasting the tires putting these pressures in. Wy then would VW state the higher pressures? Because I have put a larger tire on the 18" rim should I reduce the tire pressures????


----------



## Caribmon71 (Apr 22, 2005)

Your tire guy is an idiot. I'm sure he isn't smarter than the engineers over at VW. Stick with VW's specified tire presure. I keep mine all the time at 44 at the rear and 39 at the front, as per the door label. Remember, this vehicle weighs a lot. I believe over 6,000lbs.
I wasn't exactly happy with the wear on my Continentals, but at least they wore out evenly. Keeping them at the recomended pressure will also save you money on fuel. It will be a bit bumpier ride, but safer, I bet.
Good luck.


----------



## Bigtop (Jan 8, 2004)

*Re: (Caribmon71)*









I agree. I just got an e-mail response directly from Continental-
"Our current recommendation is to never use a tire inflation pressure 
lower than the Original Equipment specification, regardless of the change from Extra Load to Standard Load. This is to more closely match the original tire's spring rates. As for the tread, the width would not change as a result of using a narrower rim."
They handle wonderfully and are very quiet and smooth. Although I have to admit it has been so long ago since I rode the OE Spec Contact 4x4 when they were new to remember the difference in quietness. It is very apparent though in the handling department, they are absolutely planted on the road. I would obviously not recommend these for anything other than summer tires. I have some 17" rims that I put some Bridgestone Dueller A/T Revo 265/60/17 on. They are great for offroad and snow winter conditions, but not so hot on the handling department.
So in a synopsis: 285/50/18 sized tires work fine on the OE 18"x8" spec rims with no clearance problems and you must keep the tire pressures the same as recommended by VW even if the width is different to the 255 size.
Amen


----------



## henna gaijin (Jun 30, 2005)

*Re: (Bigtop)*


_Quote, originally posted by *Bigtop* »_ So in a synopsis: 285/50/18 sized tires work fine on the OE 18"x8" spec rims with no clearance problems and you must keep the tire pressures the same as recommended by VW even if the width is different to the 255 size.
Amen










Pics?


----------



## Bigtop (Jan 8, 2004)

*Re: (henna gaijin)*


----------



## Bigtop (Jan 8, 2004)

*Re: (Bigtop)*

Uhoh! I'm a bozzo. I thought you were supposed to insert a hyperlink to an .html page where the photos are on website, between the







symbols. What am I doing wrong??


----------



## henna gaijin (Jun 30, 2005)

*Re: (Bigtop)*









I don't know








If I go to the URL : http://www.70crowndrive.com/Touareg.html I can see the pics, but can't get them to post.
Anyway, thanksfor the pics.



_Modified by henna gaijin at 9:01 AM 5-19-2006_


----------



## Emmasis (Dec 23, 2004)

*Re: (henna gaijin)*



henna gaijin said:


> I don't know
> 
> 
> 
> ...


----------

