Tire Wear: Are Your Tires Worn Unevenly?

Hi, on my 2002 Passat with a mileage of just 245,000 km, all four tires are worn down extremely unevenly on the inside edge to the point where the tire cords are visible.

A DTS coilover suspension system has been installed for approximately 3 years, and the tires have also been in use since then. They are Dunlop tires, size 225/35 R19. The tire pressure is around 2.8 bar.

So far, I haven't experienced any problems; the vehicle runs and drives well.
The tire was replaced both back then and about 3 months ago, because one tire had already been worn out 3 months prior.

I'm now suspecting the shock absorbers because the car feels a bit "floaty," although it might just be my imagination since I recently installed the winter tires (15"). Can faulty shock absorbers cause this kind of issue?

The tires look like they've been scuffed, but there's definitely nothing rubbing or scraping.

Could worn control arms also be the problem? I've had the vehicle for 145,000 km, and the control arms haven't been replaced during that time. However, the rear tires have a similar appearance, and there are no noises coming from the front axle...


Here are some photos of the tires (the rims don't have any dents, it just looks that way in the pictures).

It seems the wheels are definitely wearing more on the inner edge. This is likely caused by excessive negative camber. Those who modify their vehicles too much sometimes have to pay the price later.
So, either adjust the suspension properly, or better yet, use a suspension system that is suitable for the vehicle.
Herbert.

Hi Herbert, the alignment was only properly adjusted by a specialized workshop.
The suspension system is a good fit for the vehicle...

What else can be done?


Sven.

First, it's necessary to determine whether these are dynamic or static errors.
The argument against static adjustments is that the toe and camber were recently adjusted correctly.
Unfortunately, dynamic processes are very difficult to identify.
However, picture 4 shows a tire that appears to have been "stamped," which suggests dynamic processes are at play. In this case, I would suspect a faulty shock absorber. It could also be related to worn-out wheel suspensions.
Image 3 shows a tire that seems to be running almost parallel to the tread. You wouldn't normally expect such extreme lean to cause something like this. In this case, I suspect a damaged suspension component.

Try it out with new tires:
Inflate them to the maximum allowed pressure (short-term... for the test... you can go significantly higher), so that the tire only rolls on the center part (balloon tire). Create a puddle of water on a dry, level road surface. Now, drive through the puddle and let the car roll; the tread pattern should then only show the middle of the profile. -> Everything seems okay so far.
Now, do the same thing again, but brake heavily after driving through the puddle. If the rolling pattern now changes towards the inside, then the suspension components are defective.
Finally, you can try accelerating extremely hard immediately after passing through the puddle. If you're "lucky," you might see a different pattern here as well.

Hi!

Well, it doesn't look healthy.

Auf dem untersten Foto, die abgenutzten Stellen in den gleichmässigen Abständen spricht irgendwie schon für def. StShock absorber.

I'm not really sure what else to say.
Do you have any specific requirements regarding tire pressure? Perhaps the tire manufacturer specifies a recommended air pressure, which used to be common in the past.
My gut feeling tells me that 2.8 is too low.
The car will then become very stiff.
But that's the price.

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What else can one do?

You mean less.

I see the issue with air pressure similarly to Steffen... it almost looks like the contact patch of the tires shifts towards the tire sidewall during turns, to the point where the sidewall makes contact with the ground.

Of course, the driving profile also plays a role.

How much deeper is the gun chamber? It might not be possible to adjust the pre-ignition curve within acceptable limits.

The rest of the chassis is probably also ready for the scrap heap.
Ultimately, what you do with the craft shed is up to you.
Personally, I would revert to a sports suspension.
Too much is just too much... it provides absolutely no more grip on the road surface... not to mention everything else .

Unfortunately, that's the case.

It would be interesting to see the Achs values. Please upload the log file if possible.

Depending on the lowering, I doubt that the rear axle geometry is still within its optimal range, as with the 3B/G system, it can only be adjusted indirectly and not "finely tuned."

As mentioned before, driving style also plays a significant role; if someone likes to drive quite quickly through curves, they naturally have to pay a certain price for it.

It would also be interesting to know which picture shows which tire (mounting location).

Hello, thank you for your responses!

By the way, the car I'm modifying is a well-maintained vehicle (as long as my wife allows it, considering she has a 6-year-old son!), and it only has a coilover suspension and wider tires; everything else is original.

I've also considered switching to a 3AA Passat, but the way my car is used by my wife and son has discouraged me. Besides, it's nice to keep older models around sometimes; you don't always have to get something new right away.

Since I'm not planning to spend that much money on new tires in those large sizes (around €650-€700), it's no longer worth it for this old bike...it's been around for a few years now.

I'm putting in new shock absorbers now (Bilstein B4), and the original springs are going back in along with the original 15" 195-size winter tires, and then that's it, no more tinkering .


During the installation, I'll inspect the entire suspension system and potentially replace some parts. I'll then monitor its performance throughout the winter, and a wheel alignment will be done afterwards.

During the TÜV inspection in October 2013, the inspector was still satisfied with the control arms and the entire suspension system; it passed without any defects.


I'll have to try that thing about the "over-inflated" tires sometime.



Best regards, Sven.

If you're already resorting to series springs (which really surprises me ),...
You should also use dampers that are compatible with the vehicle's identification number to ensure that the suspension system works harmoniously.

Whether that is the case for the ones you mentioned, ???

For example, Sachs Advantage tires are slightly harder than the standard ones, but they harmonize perfectly with the vehicle... and they are also very durable.

Is that a Passat 4Motion?
Then, depending on the lowering

Quote:

, I doubt that the shock absorber at the rear is still functioning properly within its design parameters, because with the 3B/G system, it can only be adjusted indirectly but not "finely tuned"

, perhaps also for the rear.
hg
Herbert.

Is it a front-wheel drive vehicle...?

The Sachs Advantage shock absorbers seem to no longer be available new; the auction house is likely selling off remaining stock.

There is nothing to be found at Sachs itself.


Sven.

If the wheel bearing housings are originally attached to the axle body, it becomes difficult to explain the uneven wear on the rear tires. At least, it shouldn't be due to a lowering kit, as the camber doesn't change significantly due to the movement of the axle.
hg
Herbert.

Interesting... it seems they've probably been removed from the program.

I don't know your requirements... For the standard requirement, the normal (standard) settings would be perfectly sufficient. However, you should be aware that the vehicle may exhibit some swaying when cornering .

I switched to Avantage when I had the front axle refurbished (specifically the control arms) at 220,000 km. The difference compared to before was actually surprisingly small... I expected more.
It should be mentioned that I replaced the shock absorbers as a precautionary measure.
to avoid having to disassemble the upper console a second time.

Herbert wrote:

... At least in that regard, it shouldn't be due to lowering the vehicle, as the rake angle (almost) isn't changed by the axle movement. ...

I agree with that. That's why I still believe the rear suspension mounting points are causing a problem. It's a huge issue with the Passat. This would also explain the lack of precision when driving.

In addition, I would like to point out that the very short tie rods normally form an extended angle with the steering gear when they are in the zero position.

If a wheel collapses or rebounds, the angle to the steering linkage changes, which results in a track correction (relative to the length of the control arms or the design) that is intended to stabilize the vehicle.

However, when the vehicle is lowered to its maximum extent, both ends of the tie rods are angled upwards.
When accelerating, the vehicle body sags, which reduces the angle and increases the distance between the left and right steering knuckle pivot points, forcing the vehicle into a greater amount of toe-in.

With the standard suspension, it's exactly the opposite because the angle increases starting from the zero position.

For vehicles with "standard" length tie rods, this effect is significantly less pronounced.

If a vehicle like a VW Passat 3B, Audi A4, A6, or A8 exhibits a tendency to drift laterally when encountering long undulations on the highway, it could indicate an incorrect toe-in setting.

With this adjustment, the immersion depth of the tie rod ends into the wheel bearing housing is changed.

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Axis values would be interesting to see. Please upload the log file if possible.

That would be really helpful.
hg
Herbert.