ICONCLS

I have a nasty pull to right after mounting Michelin Pilot Sport A/S.

Here is the thread from the RS 6 board for some background:
<a href="https://forums.audiworld.com/rs6/msgs/1831.phtml">My Right Pull Hell</a>

Since this thread disscussion, I would add that I just had a road force balance done on all 4 tires yesterday and that came up clean.

Any references, help, insight would be greatly appreciated.

PaulW

But all of your troubleshooting methods have not yielded results that would show that you have a bad belt.

Alignment was dead on via the dealer (who really is the only one that knows how to do this as far as I can tell) and when you swapped tires to another set, it went away.

That tells me it's a tire (s). However, you swap them front to back and left to right with no change in pull. Very weird.

I don't know if I have any sugestions. All I can say is that it appears you have the symptoms of a bad belt in a tire.

pw

ICONCLS

what really has me stumped is, if it were a bad tire, we should be able to swap it around and get the car to pull left, but no can do.

I must say, I have less faith in the dealer than I do the tires.

PaulW

I don't know, something to check.

ICONCLS

Yes and everything appears nominal, weird isn't it, we're all stumped.

mclarenm8d

Your symptoms remind me of an oddity with my A6 4.2. The note on tire pressure having an impact has led me to believe there is an issue with tire compliance being different across brands having an effect on the car in steady state. As a gross example of this effect, I've heard that for some models of BMW's going to a low profile tire can cause oddities in response that are hard to rectify.

FWIW, in Chicagoland, a car that is truly aligned properly will always pull to the right. But I have noticed the tire pressure effect.

Based on your previous posts, I can assume that you know more than the average bear. So, here is a test case:

Find a level surface and note if the car "turns-in" easy going in one direction but feels like it climbs over the hill in the other. This is a dead-giveaway that the caster or camber is cocked-up on one side. If you don't notice this, but there is definitely a steering input required to keep the car going straight, suspect steering wheel being off relative to toe settings or the front and rear wheels having a toe mismatch.

My guess? Your car is aligned dead nuts on, Chicagoland roads suck, and your new tires are amplifying the Chicagoland roads suck factor. Going to high pressure helps to alleviate the Chicagoland roads factor.

ICONCLS

Thanks, from what you describe, it feels more like a toe issue, I'll test some more.

PaulW

I would consider bringing it to them for testing, make sure he is the guy who does it.

Did you get as-found and as-left readings? I always ask for them and they give them to me.

If you post in the Chicagoland forum, Dave will most likely respond.

pw

ICONCLS

Thanks...will do.

gondar

Check for disc temp differentials-look for brake drag esp front. Feel discs after driving and coasting to a stop.

Does pull change under light braking?

Measure with a spring scale or the MK I finger steering effort L and R with wheels on ground and unladen. Some obscure rack valving bias problem?

Check for unusual ball joint/tie rod end friction.

Check the circumferance of all four tires. I know this sounds silly.

If all else fails, wait till summer and enter the novelty "backwards" dirt track event at the county fair, I guess.