# Technical Description - Phaeton Air Suspension



## PanEuropean (Nov 3, 2001)

There is an interesting article summarizing how the Phaeton air suspension system works at the Society of Automotive Engineers (SAE) web site, here is the URL: http://www.sae.org/automag/tec...3.htm
It is the second of the three article that appear on that page.
PanEuropean


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## Corradodrvrfnd (Feb 15, 2002)

*Re: Technical Description - Phaeton Air Suspension (PanEuropean)*

for the lazy...
Continental gives Phaeton a lift

The Phaeton's Continental air suspension component set is a refinement of the Audi Allroad Quattro system. 
The Volkswagen Phaeton is the first vehicle in the luxury segment to have Continental Teves' four-corner air suspension chassis with continuously variable semi-active damper control. Continental says the Electronic Air Suspension (EAS) eases the conflicts that exist between optimal riding comfort and agile handling. It adjusts damping force on every wheel variably, depending on the load and driving situation, and also automatically adjusts vehicle height. 
The system's intelligent control adjusts the damping force for each wheel end within 10 to 15 ms for "exceptional control." The goal was to decouple the vertical motion of the wheels from the car body so effectively that it provides a new benchmark of comfort and handling. To make this possible, the Phaeton has wheel acceleration sensors on the shock absorbers as well as two sensors at the front and one in the rear to measure body movement. The EAS control unit, which also processes data for engine management, brake system, and Electronic Stabilization Program, uses the wheel and body information to calculate the best damping force for each wheel. 
As, for instance, the front axle hits a bump and deflects, it tries to lift the front end; a countering very low damper pressure level is selected to provide the wheel with as little resistance as possible so that the Phaeton's body is affected less than with a traditional suspension. When the wheel has reached the top of a bump, the body is "braked" in its upward motion by high damping force in the rebound stage and brought back down together with the wheels as quickly as possible. As a result, the car body moves much less on the whole. 
Via other sensor signals, EAS control electronics can recognize, for instance, whether the driver is steering into a curve, or the vehicle is accelerating or being braked. The chassis control unit immediately sets the appropriate damper characteristic to minimize the body's rolling or pitching motion and guarantee optimum riding comfort and safety. 
The air-supply module for Continental's air spring system consists of a compressor, solenoid valve, control device, solenoid switch, and noise control. 
The Phaeton driver can select between four fixed damper settings ranging from soft to sporty or firm. However, when sharp handling is required, the chassis computer can temporarily provide higher damping forces even when the comfort setting is selected. 
Conventional steel-sprung-chassis ride height is always a compromise between the optimum setup for light and heavy vehicle loads. The Phaeton chassis solves this classic conflict in setup because the car body is consistently supported by air springs filled by a compressor regardless of load, ensuring consistent spring travel at all times. The technology, which was already implemented in Audi's Allroad Quattro, was refined for the Phaeton. Because the air springs are surrounded by an aluminum guide, the walls of their bellows can be made of exceptionally thin material for exceptionally sensitive response and thus ride comfort.


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## whealy (Nov 15, 2004)

I was looking for more information on the Phaeton air suspension. Ultimatly I foudn this thread, but i thought I would add the other articles I found ...

Volkswagen Phaeton ? Stepless four-wheel air suspension standard equipment 

Top engine versions have 4MOTION four-wheel drive as standard
Combination of comfort and dynamics sets new standards 
As with passive safety, Volkswagen has also laid down the highest available standards for the active safety elements (running gear, drive unit, brakes and steering). The high level of driving safety, and the dynamics of the Phaeton which goes hand in hand with this, were brought about in conjunction with extremely good comfort characteristics. The new, standard, fully-independent running gear with air suspension is in part responsible for this. In addition, in the case of the more powerful engine versions the 4MOTION four-wheel drive system with Torsen differential is fitted. 
The aim of the running gear development engineers was a suspension system which meets the most exacting demands in terms of ride and driving dynamics. For this, air suspension systems with controlled damping are outstandingly suited, as they offer numerous advantages over traditional steel spring systems. 
At higher speeds the running gear is automatically lowered 
The levelling adjustment of the air suspension permits a soft, always even and thus comfort-oriented configuration of the suspension, benefits in terms of driving stability, the defined lowering of the vehicle at high speeds and thus a reduction of consumption and rolling tendency. In addition the air suspension optimises the Phaeton's driving characteristics over bad roads by raising the vehicle. The physical characteristics of the air suspension mean that the spring rates automatically adjust to the current load, thus also automatically assuming the function of a classic self-levelling system. As a result, the ride remains equally good under all load conditions. Furthermore, differences in driving dynamics are reduced quite independently of the current payload. Since the damping is steplessly controlled, there is a significant improvement in ride and driving safety; extreme driving situations are also made more controllable through specific interventions in the damping control. 
The basic design of the running gear comprises a four-link front axle and rear double wishbones. The air suspension itself consists of the following basic elements: a total of four pneumatic suspension struts at the front and rear wheels, an air compressor, a pressure reservoir, a control unit, a total of four level sensors at the front and rear wheels, two body acceleration sensors at the front wheels and one at rear. 
The air suspension offers a unique symbiosis of comfort and dynamics 
The core elements of the system are the four air suspension modules. These units ensure a very gentle response to every wheel movement. The desired low spring rate is ensured via an additional volume and a special piston shape, positively influencing the dynamic characteristics of the air suspension. 
In addition the damping force at each strut is adjusted in milliseconds to the current requirement via an electrically-controlled valve integrated in the piston of the twin-pipe gas pressure damper. The optimum damping force for direction and stability is ascertained among other things by wheel acceleration sensors at the dampers and the three axle acceleration sensors. An intelligent structure which makes the new upper range saloon unusually agile in handling, but at the same time extremely comfortable. Thus the air suspension with dynamic damping has made possible a running gear design in which the driving dynamics does not come at the expense of the ride. 
The particular design and positioning of the suspension strut mountings ensures that the dampers are insulated from lateral forces. The consequence is a perceptibly improved response, and ultimately an out-of-the-ordinary ride comfort. 
The driver can choose between two height levels and four damper configurations 
In all the Phaeton offers three different suspension heights: normal level (NL), high level (HL) 25 millimetres above normal level and lowered level (LL) 15 millimetres below normal level; this is controlled automatically in line with the vehicle speed, so as to optimise the driving characteristics and the fuel consumption at higher speeds (from 160 km/h). 
Naturally the driver can also intervene manually in the running gear configuration. Behind the gearshift on the centre console are located the operating elements for level and damper control, easy to get at and intuitively understood. Via these buttons the driver has two levels (NL and HL) and four damper configurations (base, comfort, sport, sport2) available. The damper control itself is based on the so-called skyhook principle, which minimises the overall body accelerations and ensures a constant level whatever the road. 
The range of active safety elements is rounded off by the running gear control systems which also intervene electronically. These comprise the ESP (electronic stability program), the brake assist, the ABS (anti-lock brake system), the EBD (electronic brake force distribution), the TCS (traction control system), the integrated (two on front-wheel-drive, four with 4MOTION drive) EDL (electronic differential locks) and the EBC (engine braking control). All these systems are standard equipment on the new Phaeton. An automatic tyre pressure monitoring system (TPM) is also available as an optional extra.


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## whealy (Nov 15, 2004)

and ...

Pneumatic suspension as standard guarantees comfort without compromising dynamism, separate temperature control, even in the rear, with 4-zone Climatronic 
Sweden. Here in Lapland, close to the Polar Circle, over 2 000 kilometres by road from Wolfsburg, Volkswagen is testing its new luxury class saloon in winter conditions. Running gear and climate control are on the checklist compiled by the development team. More precisely: the fully pneumatic suspension on the front and rear axles and 4-zone Climatronic. Now, shortly before Christmas, the test grounds are veiled all day long by the endless polar night. Only the blanket of snow, averaging 25 cm thick, reflects a shimmering of light in the daytime darkness. The temperature is between ?8 and ?18 degrees, and can even drop as low as -45 degrees. Ideal conditions for the test vehicle, precisely because they are so hard. The first test drives will start at about 17.30 hrs. Snow has been cleared from a frozen lake to form the course over which the crew will drive the saloons. 
The new, fully pneumatic suspension 
The icy surface appears to be perfect terrain for fine-tuning the running gear and for gathering information on the handling of the front-wheel-drive and all-wheel-drive luxury class saloons. But for Volkswagen, such work has long been completed. The developers are much more interested in checking the synchronisation and the stability of the systems one last time. And these systems are not trivial. When the Volkswagen Phaeton is launched next Spring, it will be equipped as standard with a pneumatic suspension possessing excellent dynamics and comfort characteristics. "The objective", according to the internal definition of the responsible running gear development engineer, "was to produce a suspension system that meets the most exacting demands in terms of ride comfort and dynamic driving. Air spring systems with regulated damping are excellent for this as they offer numerous advantages over conventional steel spring systems." 
Fundamentally, with regard to its overall characteristics, the air spring system must be viewed differentially and evaluated in its own right. The physical and thermodynamic properties of the air enclosed in the spring bellows must be examined in extreme detail. Add to this the integrated level control system, which maintains the vehicle at a specified height (or one set by the driver), regardless of load. In addition to this, the freely variable mapped damping system demands special attention. Due to their physical properties, the air springs automatically adapt the damping rate to the current load. This means: 

Ride comfort remains optimal regardless of load 
Load-dependent variations in handling are reduced. 
The level control feature of the pneumatic suspension 

Allows a soft and comfort-orientated suspension 
Allows the vehicle to be specially lowered at speed, both to improve aerodynamics and to lower the vehicle's centre of gravity, so improving driving stability even at high speeds 
Increases ground clearance on poor surfaces by raising the vehicle 
The freely variable, mapped damping system 

Improves ride comfort and driving safety 
Ensures superb handling even in extreme driving situations thanks to programmed damping control 
The sum of all these advantages caused Volkswagen to decide to develop the Phaeton exclusively with an exceptionally sophisticated, high-quality pneumatic suspension. In winter 2001, one of the last test drives for this system will be made on the ice of a frozen lake in Northern Sweden. The basic layout of the running gear is a four link front axle and a newly developed trapezium link rear axle. 


VW Phaeton Arctic Winter Testing Page 2 of 3: previous page | next page 


VW Phaeton / © GCF 

VW Phaeton Arctic Winter Testing
Press Release
01-13-2002

The suspension system consists of the following basic elements: 
Four air spring struts on the front and rear axles 
An air supply unit 
A pressure accumulator 
A control unit 
A total of four level sensors on the front and rear axles 
Two body acceleration sensors on the front axle 
One body acceleration sensor on the rear axle 
A total of five air lines 
The core elements of the system are the four air spring modules with a completely new type of air spring bellows. These bellows are extremely durable, but still guarantee a very soft response to any movement of the axle. The necessary low spring rate is reliably provided by an additional volume and by a special piston shape, thus positively influencing the dynamic response of the air springs. The special design and location of the suspension strut support bearing (upper connection to body) ensures that transverse forces are kept away from the dampers. This results in noticeably improved response characteristics and ultimately an exceptional level of ride comfort. 
Moreover, the damping force at each suspension strut is adapted to the actual requirements in a matter of milliseconds via a piston in the two-tube gas-filled shock absorbers and an electrically controlled valve. The damping force, which is computed to the optimum value according to direction and intensity by, amongst other components, the wheel acceleration sensors on the shock absorbers and the three body acceleration sensors. A complex technical construction that is nevertheless easy to appreciate – the new saloon is exceedingly agile in handling, but remains extremely comfortable. The pneumatic suspension has led to a running gear configuration that does not compromise ride comfort for dynamic driving. The intelligence of the air spring system lies in the pneumatic suspension control unit. There, all signals gathered by the sensors are analysed and linked up to data from other vehicle subsystems. Data is exchanged via a CAN bus. In short, the control unit regulates the air springs and the shock absorbers so that the saloon's ride height and vibration damping are properly synchronised. To do this, the control unit continuously exchanges data with other control units, for example with the ESP control unit, the engine and gearbox control units, the combi-instrument or the central control and display unit. The latter also displays the current air spring system settings for the driver's information. In addition, a diagnosis interface provides assistance, for example for servicing the air spring system. 
In principle, the Volkswagen Phaeton has three different running gear height settings: 

Standard level 
Raised level – 25 millimetres above standard level 
Lowered level – 15 millimetres below standard level. This is automatically activated depending on the vehicle's speed to optimise handling characteristics and fuel consumption at high speeds (from 160 km/h). 
However, the driver is able to set the system individually. Behind the gear lever in the centre console there is an easily accessible and intuitively comprehensible control element for level control and shock absorber regulation. These buttons provide for two ride heights (standard and raised) and four shock absorber maps (basic, comfort, sport, sport2). The shock absorber regulation itself is based on the so-called "skyhook principle", which minimises body acceleration and guarantees a constant ride height regardless of road conditions.


Not only the pneumatic suspension is being tested in the snow and ice. The development engineers are also testing the new 4-zone Climatronic under extreme climatic conditions. This system offers three important advantages over the systems used to date: For the first time, passengers in the rear are able to control the air conditioning for the left and right-hand side individually. The designation 4-zone Climatronic is derived from the four variable areas. In addition, the cooling or warming air is indirectly fed into the defined zones through automatically opening and closing vents so that it does not cause a draft. 
Finally, an effective function is integrated that uses humidity control to automatically reduce the degree to which the windows mist over compared to systems on the market today. The technological concept and the manner in which the new Climatronic works can be summarised as follows: 
In the first step, the outside air drawn in is largely cleaned of pollutants by two particulate filters with an activated charcoal element. A twin-flow blower splits the primary air flow. Then a complex air conditioning system with 25 electric positioning motors provides the perfect control for the air distribution. 
In the front area, direct ventilation ensures that the vehicle is heated or cooled as quickly as possible. However, this direct inflow of air is only needed briefly. Once a certain temperature level has been reached, it is more important to distribute the air indirectly – that is free from drafts and not directed at the driver and front-seat passenger. For this reason, the "blower vents" that we all know from every passenger car automatically close and are completely hidden by wooden trim panels once certain climatic conditions have been reached. A ventilation strip stretching around the entire interior then ensures draft-free air circulation. 
Special attention was given by the air conditioning engineers to the rear of the interior, which – as indicated – provides for the very first time individual temperature control for the two outside seats. The most important component of the rear 4-zone Climatronic is a multi-functional distributor housing. The distribution boxes integrated into this feed the selected temperature setting to the required vents in the rear. In addition, special heater elements in the distributor housing guarantee that the system responds quickly. The level of the individual air temperature zones is controlled by seven so-called "air vent temperature sensors". 
While the refrigerant circuit of the 4-zone Climatronic will not be needed very much in Sweden's polar winter, the engineers are able to test the heating circuit more intensely. Volkswagen has integrated a newly developed fully aluminium heat exchanger into the air conditioning system. This is extremely lightweight and with a heat output of 8.25 kW exceptionally efficient. 
Significant for the series production air conditioning system is the fact that the windows remain clear under almost all operating conditions. To prevent misting or to demist the windows, the fully automatic air conditioning system directs hot air through the demister vents, in particular at the windscreen. Very often when this happens, there is the unpleasant side-effect that the headroom becomes too hot. For this reason, Volkswagen has taken a different approach with its luxury class saloon. 
Windows mist up when the temperature of the glass drops below the dew point. The dew point varies and depends on the humidity of the air inside the vehicle. The reason for this is that the air inside the vehicle always contains a certain degree of moisture. Whether and for how long this moisture remains in the air depends on the air temperature. The dew point is understood as being the temperature under which moisture from the air condenses and returns to the liquid phase. This happens when condensation forms on a cold surface –cold, misted-up windows, for example. With the new 4-zone Climatronic, Volkswagen tackles this problem head on. 
Firstly: A minimum temperature difference between the dew point and the temperature of the windows is guaranteed in the saloon, so that only a minimum amount of hot air needed for an optimising basic temperature adjustment is fed in. This prevents the headroom from being heated up too strongly. Secondly: Humidity is measured by a sensor in the interior mirror mounting bracket. The Climatronic control unit uses a reference temperature measurement to calculate the moisture content in the air and a comparison with all parameters to calculate the dew point. At the same time, the temperature of the inner surface of the windscreen is measured by means of an infrared sensor. As soon as there is a risk of the temperature of the windscreen dropping below the safety margin for the dew point, the air conditioning system will reduce the humidity in the air. Additional regulatory parameters such as the angle of the defrost valve and the airflow throughput guarantee that the windows will remain clear in almost any conditions. All this happens unnoticed by the vehicle's occupants and without causing drafts.


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## rmg2 (Jan 23, 2004)

*Re: Technical Description - Phaeton Air Suspension (PanEuropean)*


_Quote, originally posted by *PanEuropean* »_There is an interesting article summarizing how the Phaeton air suspension system works at the Society of Automotive Engineers (SAE) web site, here is the URL: http://www.sae.org/automag/tec...3.htm
It is the second of the three article that appear on that page.
PanEuropean

I wonder if the Bentley GT uses the same supension?


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## PanEuropean (Nov 3, 2001)

*Re: Technical Description - Phaeton Air Suspension (rmg2)*

Exactly the same, AFIK.
Michael


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## Paldi (Sep 4, 2004)

*Continental Phaeton Air Suspension System*

Here's the 2002 press release and the website of the manufacturer. More info is available in this Forum's Table of Contents.








Website:
http://www.conti-online.com/ge....html

Press Release:
VW Phaeton glides into the upper class of cars on an air suspension chassis from Continental 
Effective skyhook control thanks to continuously variable dampers

Hannover/ Wolfsburg, May 2002: The Volkswagen Phaeton brings groundbreaking technology to the upper class of cars. It is the first limousine of this market segment to have a standard four-corner air suspension chassis with a continuously variable semi-active damper control. Developed by Continental Automotive Systems as systems supplier in cooperation with Volkswagen, this chassis, the Electronic Air Suspension EAS, eases the conflict of goals that exists between optimal riding comfort and agile handling. It adjusts the damping force on every wheel variably, depending on the load and driving situation, and also automatically adjusts the height. This technology will be debuting in other German premium class cars this year.

The intelligent damper control of the Continental system individually adjusts the damping force on each damper within 10 to 15 milliseconds, thereby making an exceptionally effective skyhook control possible. The term skyhook clearly reflects the basic principle of this system. The goal is to decouple the up and down motion of the wheels and axles from the car body so effectively that it travels as smoothly as if it were hanging from a hook in the sky, even on rough roads.
To make this possible, the Phaeton has wheel acceleration sensors on the shock absorbers as well as sensors to measure the car body movements - two on the front end, one on the rear end. A control unit, which also processes data for the motor management, brake system and electronic stability program ESP, then uses the information to calculate the best damping force for each wheel individually.

Example: The front axle hits a bump and as it deflects, it tries to lift the front end. At this moment a very low damper pressure level is set in the Phaeton to provide the wheel with as little resistance as possible as it deflects so that the car body can follow the upwards motion of the wheel smoothly and comfortably. When the wheel has reached the top of the bump, the body is braked in its upwards motion by high damping force in the rebound stage and brought back down together with the wheels as quickly as possible. As a result the car body moves much less on the whole.

From other sensor signals, the control electronics recognizes in turn whether the driver is steering into a curve, whether the vehicle is accelerating or being braked. The chassis control unit immediately sets the appropriate damper characteristic for this driving situation, thus minimizing the rolling or pitching motion of the body. In this way, the optimum riding comfort and best driving safety is guaranteed for every road condition, depending on the driving situation. In addition, the driver can select between four fixed damper settings, ranging from soft to sporty-firm. In situations where a great deal of handling is required, the chassis computer is still in a position to temporarily provide high damping forces also when the comfort setting has been selected.

A second factor that is decisive for comfort and safety is the vehicle load. Conventional non-adjustable chassis with steel support springs can at best try to achieve a good compromise between "empty drives" and those with the maximum loads. In this regard the Phaeton chassis also solves classic conflicts of goals, because the car body is supported by air springs that are filled by a compressor, depending on the load. In this way, there is an automatic height control that ensures consistent spring travel at all times. This technology, which has already been implemented in the Audi allroad quattro, was refined for the Phaeton. Since the air springs are surrounded by an aluminum guide, they can be manufactured of exceptionally thin material. The thin wall of the air bellows provides exceptionally sensitive response and top ride comfort.

The control unit regulates the body height automatically, depending on the vehicle speed. At speeds exceeding roughly 140 km/h, the Phaeton drops about 15 millimeters compared to the normal height in order to optimize the driving properties and aerodynamics. At the push of a button, the driver can raise the body by 25 millimeters over the normal height to prevent damage to the vehicle in parking garages or on bad roads. This high position is also monitored by the chassis computer. If the Phaeton exceeds 120 km/h, the body automatically drops back down to the normal height.



_Modified by Paldi at 8:33 PM 2-19-2005_


_Modified by Paldi at 8:35 PM 2-19-2005_


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## brosen (Jun 21, 2009)

*Re: Technical Description - Phaeton Air Suspension (PanEuropean)*

Today I was checking the Air Suspension in the car and the P/N for the Front one is *3D0 616 039 Q*, then I checked the price at http://www.1stvwparts.com and the results is attached:
*3D0616039Q $1,550.62 $0.00 $1,436.27
Front suspension - Lower control arm - Strut
Strut, phaeton, 4.2l, left 2004
*
My understanding is that on the 2004 Phaetons suspension parts were discontinued and new ones are required, but based on the information from the online store they might be available ?, please somebody could confirm if the P/N I have is the old one (discontinued) or the new one (I do not think so) ?, thanks


















_Modified by brosen at 9:39 PM 8-17-2009_


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## chillson (Sep 6, 2010)

*Air Spring/Ride Setting Question*

Several members have reported failure of the air springs in previous posts. Although rare, this repair can be very expensive and even impossible due to the availability of parts. Because of this, I want to do whatever I can to reduce the chances that my air springs fail (if that is possible). Does anyone believe there could be a correlation between the ride setting (let's call them Comfort I, Comfort II, Sport I, and Sport II from left to right) and the failure rate of the air springs? I was hoping any members that have had their air springs fail could reply back with their ride setting habits. For example, if you always keep it set to the firmest setting, reply back with Sport II (softest setting would be Comfort I, etc.). Also indicate if you adjust (change) the setting often while driving.

I may be way off base with my theory, but, I keep mine set to Comfort I (softest) for two reasons. Firstly, I drive mainly long, straight, highway miles and the comfort setting is the most comfortable. The second reason is my fear that driving in Sport II (firmest) could increase the chances of damage to the air springs if I hit a pothole or other road hazard due to the increased pressure within the spring.

Am I over-thinking this, on to something, or just wrong? Thanks...Jay


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## calmone (Feb 15, 2006)

i keep mine on comfort. a strut failed at about 75,000 miles. i paid for one, vw for the other 3. for what it's worth, i think it is just a design failure remedied in the 05s'.


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## Jxander (Aug 5, 2008)

chillson said:


> Several members have reported failure of the air springs in previous posts. Although rare, this repair can be very expensive and even impossible due to the availability of parts. Because of this, I want to do whatever I can to reduce the chances that my air springs fail (if that is possible). Does anyone believe there could be a correlation between the ride setting (let's call them Comfort I, Comfort II, Sport I, and Sport II from left to right) and the failure rate of the air springs? I may be way off base with my theory, but, I keep mine set to Comfort I (softest) for two reasons. Firstly, I drive mainly long, straight, highway miles and the comfort setting is the most comfortable. The second reason is my fear that driving in Sport II (firmest) could increase the chances of damage to the air springs if I hit a pothole or other road hazard due to the increased pressure within the spring.
> 
> Am I over-thinking this, on to something, or just wrong? Thanks...Jay


Jay:

If you're over-thinking it and a bit paranoid, add me to the list. I essentially do the same that you are doing. However, I find that on highway trips at 70 mph plus, I like to go to Comfort II setting. If I use Sport I and II it is only for some momentary thrills. 

I also periodically go through my settings and also change the ride height based on the "use it or lose it" mentality. However, i also use this logic with my rear door windows which are rarely opened and closed under normal Florida conditions. 

I've also wondered about wheel size and tire profile on the failure of air shocks. Some owners have installed custom over-sized wheels and very low profile tires for cosmetic reasons. 

Jim X


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## invisiblewave (Sep 22, 2008)

Isn't it the hydraulic system that fails, rather than the air part? I seem to remember that the failing part is the grommet carrying the fluid line in near the top of the strut. I don't know how the struts work in detail, but I'd guess that the pressure change is in the gas part, not in the fluid.

Edit: Sorry Jim, I'm not deliberately looking for reasons to contradict you this week!


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## Jxander (Aug 5, 2008)

invisiblewave said:


> Isn't it the hydraulic system that fails, rather than the air part? I seem to remember that the failing part is the grommet carrying the fluid line in near the top of the strut. I don't know how the struts work in detail, but I'd guess that the pressure change is in the gas part, not in the fluid.
> 
> Edit: Sorry Jim, I'm not deliberately looking for reasons to contradict you this week!


Invisible:

No need to apologize about contradicting me. I'm used to that from my wife. 

Also that's the good thing about forums such as ours, we can exchange info in a non-hostile environment. However, I still plan on changing my oil more frequently than 10k as long as I use Syntec and don't use one of the "long-life oils such as used in Europe. Note I will do this even though I know I might be wasting some cash. It's the might be that concerns me. 

I believe the line you mention that attaches to the strut is an air line and not a hydraulic line. I don't think the Phaeton has any external hydraulic pressure. However, you may have had another car that combined air and hydraulic fluid in combination for shock function. You probably have SSP 275. In that it discusses the Phaeton air suspension in more detail than I care to read. Nevertheless I did find this in that pdf file



> "Full load-bearing" means that only air
> springs are used as load-bearing
> spring elements on all wheels.
> Combined suspension systems, which
> ...


Earlier in file they describe the Phaeton as a "full load-bearing" system. It appears that the only hydraulic fluid or gas in the Phaeton strut is internally encased. Not sure about the correct terminology but it seems that the air component of the Phaeton struts serves as the counterpart of a steel spring. The shock absorber component is a fairly typical sealed unit with some form of hydrauilic fluid and gas.

Jim X


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## invisiblewave (Sep 22, 2008)

If you take a look at the top of the strut, there's a small pipe that enters, someone posted that this is the part that fails and that it leaks some sort of fluid. I remember it from the height of my suspension strut paranoia. 

I, too, am well used to domestic contradiction! She recently mentioned that she's interested in "one of those smartphone things", in the same sentence as "can you make that happen". The getting it isn't an issue, but the ongoing support that will be required may well be even more taxing than trying to get my climatronic gremlins fixed.:banghead:


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## valmes (Oct 27, 2009)

http://www.volkspage.net/technik/ssp/ssp/SSP_275_d1.pdf
http://www.volkspage.net/technik/ssp/ssp/SSP_275_d2.pdf


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## ..Derek.. (Sep 11, 2009)

subscribed.. 

got a Phaeton to pick up that is laid out in the front


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## Paximus (Aug 26, 2011)

Will you be posting what happens?

Cheers,
Chris


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## imkbm67 (May 13, 2010)

*The dis assembling the air sus.*

You can see the disassembling of air suspension of Phaeton. 

refer this. 
http://cafe.naver.com/powercar/54


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## Paximus (Aug 26, 2011)

> imkbm67:
> You can see the disassembling of air suspension of Phaeton.


 Hi, do we need a logon to the forum site to see the images? 

Thanks, Chris


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## rscharf (Jan 19, 2004)

*Front Strut Failed at 80K Miles and 15 Years*



calmone said:


> i keep mine on comfort. a strut failed at about 75,000 miles. i paid for one, vw for the other 3. for what it's worth, i think it is just a design failure remedied in the 05s'.



One of my front struts failed at 80K Miles and 15 Years after it was driven off the lot. I think the good new is that since these cars have been out there for 15 years now that there are some good replacement rebuilt ones out there for decent prices. I'll search the forum to see if there's newer threads about air suspension, but thought it wouldn't be bad to revive this old thread.

Robert


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