awdinut

These events have not happened in previous winters, BUT this is the first cold weather with my new wheel / tire set up...Bentley wheels that have a 41 off set with 275 40 19 tires. Now you have the background.

Whats happening is that when its about 30 degrees or less outside, and I back out of my parking space for the first time in the morning and turn to the left (but not hard over) while going slowly forward there is a series of loud bangs or pops and the car is thrown sideways (and me in the seat) a bit with each one. It feels like something binds-up then breaks free. Or maybe like what scrubbing would be if in super slo-mo and EXTREMELY multiplied in moment of force...(does that even make sense ?) Or like some clamitous CV joint problem.

Well, thats the best I can describe it. But the curious thing is that if I were to drive for just a few blocks and try to replicate the event the car behaves normally; like something has warmed up or loosened up and the ambient temp is no longer a factor. And on mornings that are 'warm' like 40F it doesnt happen at all.

Had it in to the shop and they put it on the lift and spun the wheels to feel for something in the CV joint, and turned the weels from side to side; but everything was smooth and normal.

It will occaisionally exhibit the behavior in reverse.

They have no theories and say they have to experience the phenomenon to have any idea...which means leaving my car with them overnight outside in an unprotected area, which I am not wanting to do unless all else fails.

And I think things are getting worse; which is to say the threshold temp has climed from about 20F. And I think more pops per revolution of the wheel.

So, what could it be ? Could the offset and / or larger tire contact patch be damaging something in my drive train ?

Mister Bally

I would first determine if it reeally is temperature related or an amazing coincidence. In other words, have them keep the car protected indoors and they can try it in the morning even in warmer temperatures.

By your description, a 30°F temperature swing would not likely make a difference.

Maybe it is a locked up rear or inter-axle (center) differential that is somehow becoming locked when it shouldn't. Who knows, maybe VCDS can reveal something as well.

mishar

It may be CV joint. Inspecting it on a hoist without any toque load may not show anything. Try sharper turn and more power. That should show more than low temperature. Or you will exclude CV joint as a problem.

You didn't say if they inspected front upper links. They can make a nasty sound, though not related to the wheel spin.

Last and probably the worst would be differential. Probably middle one if the rhythm sounds like multiplied wheel spin. If there is not enough oil, settled over night and it is cold Torsen differential can create something like you explained.

MP4.2+6.0

+1 on what the other two vets said; could be any of those.

awdinut

we had 60 last week end, and even at 50F it does not do it even first thing in the morning. And as I said, after a few blocks on a cold day, if I stop and try to replicate it wont do it. No coincidence with temp. Had the wheels and tires on since Aug with no problem till colder weather.

jakematic

Did you use hub centrics or spacers when you put the new wheels on ?

My gut says something isn't tight or the temp is affecting the expansion rate of the metals.

awdinut

The Bentley wheels are hub centric bolt on from a 2012 , same as Audi except for 41 offset. Car rolls along smooth as glass except for first manouver when car is cold. No matter how far I crank the wheel over the car behaves normally no matter what the ambient temp, after it has traveled the first couple blocks in the morning.

MP4.2+6.0

I would retorque the wheels to start--simple, few minutes time, no cost.

Then I would try to isolate which end of vehicle. Maybe it's in your posts somewhere, but it's not clear to me which end it is, or if it is generalized. If it is definitely at one end, look at that differential. If generalized, look at middle/torsen. I would check any suspect diffs for fluid levels, plus (related) signs of leaking. I say this because of your tie to temperature dependency and that it goes away fairly quickly.

As far as questions, is there any history on your car of:

1. Tranny or diff repairs, or fluid changes?
2. Prior wheel bearing replacements?
3. CV/axle or drive tube work?
4. Steering rack?
5. Work involving front or rear subframes that support drivetrain?

If so on any of those items, I would investigate if something went wrong on prior work--loose parts, fluid leakage, etc.

I pretty much dismiss the wheel issues BTW, since Bentley Continentals (assuming that's what these are) and D3's are essentially the same drivetrain, just turbo'ed for the W12 motor, one notch bigger on brake rotors, and another half ton of pork to weigh it down. 275's are just the optional D3 sizing in 20's, and I've run them both spaced and unspaced with offsets from a net of ET 26 to stock ET 46. Zero issues in this area for my whole life of car, and I run it in sometimes sub zero Tahoe as well.

awdinut

Thanks for putting my mind at ease as far as the tires / offset issue...I was worried that I had ruined something expensive in the name of cosmetic vanity.

The noise, the binding-breaking-free-loud-bang-pops-throw-the-car-sideways events come from the front wheels definitely. Mostly from the front right as I creep along to turn 90 degrees left after backing out of my parking spot.

But the colder it is the more gradual the turn that will cause the phenomonon. And I get an occaisional bang going backwards. And occaisionally a bang or two when turning right with a cold car on a cold morning. But turning left with a cold car on a cold morning creates sequential pop/bang/side-slinging events per revolution of the tire.

I've sold a lot of Audis so I have driven them in all sorts of states of repair before fixing them; and if asked I would say that there is something MAJOR wrong with the CV joint...like the ball bearings are rolling around in there like Chicklets in the box. But if that were true I should think that a hands-on spin of the wheels while in the air, even not under load, would cause something inside to make a sound or a grinding feel noticable to the tech. But no. And if they were that bad how could they feel perfect all the rest of the day's driving ? Warmer temps wouldnt make it go away I shoudnt think...thats what puzzles me.

And no to the repair questions and no sign of leaking diffs.

I will have the wheels re-torqued and report tomorrow. Although ,again, it would seem that loose wheels would manifest themselves in other ways also during my daily driving. But I'll be ever so grateful if that suggestion solves the problem !

Mister Bally

Any chance a stretch bolt in the end of one of the driveshafts somehow slightly loosened up?