Hooked it up to a 3-phase electric motor driveshaft and simulated driving ~15,000 miles. She talked to a tech there, and I guess this is a pretty common problem they run into there.

 

wow that is crazy!

 

thats weard beucase i have read a number of times that putting a diffrent thread depth on a quattro system messes it up. But im guessing since no one has said anything yet that thats only true with the tt and a3.

 

Sure they didn't just shave it? That seems like a waste of time and effort.

 

I'm sure they did some shaving, but the only way to get a nice clean end tire is to run it on this system.

I personally have never liked the end result from shaved tires. Then again the only shaved tires I have seen were custom made for off-roading.

 

Hi Guys, I'm new here but thought I would chime in on this one... My previous experience with AWD systems is extensive in that I raced 2 different Eagle Talon's one with a stock awd system and one with a modified system.

When the tires have a different overall diameter the wheels will spin at different speeds. This is also true when your going around corners as the outside wheels spins differently than the inside wheel. The only time this will cause a problem is if you have a plate style LSD like a Kazz or a viscous that is trying to lock up. ON a straight long drive where your beating on the car the diff will try and lock up. With a torsen that is all gear driven that is not a problem beacuse it's a torque biasing differential so it can handle the wheels slipping at different speeds.

With a viscous style LSD (viscous like viscosity meaning that it uses a goo in the center of the diff that once hot it locks up and makes the wheels spin together) when the wheels spin at different speeds because you have one tire that is taller than the other (say one bald and one new) it will eventually wear out the lsd. The drivetrain will still continue to operate but just as an open differential style system. Some people call it 1 wheel drive or peg leg burn outs etc...

SO what buddy was telling you is right in a lot of situations however with quattro using a torsen style diff that is gear driven and will allow for limited slip situations it will not cause any lasting damage. Now get your car towed with two wheels on the ground, that on the other hand will cause you some problems.

 

Actually BOTH are Haldex systems. All VW awd's are called 4motion (passats have torsen, golfs have haldex) and all Audi's have quattro, its justan awd label.

As for the tires, you should always have 2 tires of equal tread on the front or rear together. If not, you get pull and sometimes noise the greater the differnce. This is the same for fwd, rwd, and yes, awd. Not doing so isnt the greatest. The Haldex system needs to have the tire heights withen 5% differnce from each other, otherwise it will screw up the system

 

thanks for the info 986Jim and welcome to the forums, what kind of car do u drive now ?

 

only staggered diameter? or staggered width?

 

heights matter, width doesnt