QUA77R0

Over the last several thousand miles, I have begun to experience a loud clunk when I apply the brakes when in reverse. If I am going forward and come to a complete stop and then go into reverse, everything is fine until I apply the brakes. CLUNK! It feels as if the front wheels refuse to turn for a moment and get dragged by the rear. Only lasts for a moment but can be felt and heard.

Knowing the difficulty of diagnosing intermittent problems, as it was initially, I waited until it did it every time I was parking it. Took it into the dealer where wouldn't you know it, they and I were unable to duplicate it. The dealer had a bunch of software updates as well as the sunroof update to take care of so they said they would continue to try and find it. After 3 days, the service adviser called me saying that it had "clunked" in reverse upon braking for them. They told me that it was a problem with the control arms... Again? Anyways.. they replaced whatever they had to (bad bushings, I was told)

Picked up the avant and came home. Went to park. Backed in and CLUNK... louder and more violent than before. No time to take it back as I was moving and the avant was scheduled to go on a carrier that day.

Has anyone experienced anything similar? This is a separate issue from the vibration issue that has plagued many of us and continues in the avant.

Cabal_san

Had this also. Turns out was some miss applied bolts to the control arms, i think uppers. Came from Germany like this.

A few were replaced with the correct size and then a thorough undercarriage inspection by the SA re-torqued all. This was a while back. I remember posting on this at AZ. I'll see if I can re-link. I posted the actual ticket info with this detailed.

But it was exactly the same. Started off clunk in reverse, I thought was bad break piston. YMMV.

Good luck

here you go:

http://www.audizine.com/forum/showth...=1#post5851202

post #12 has the info...

snagitseven

I had something similar but when going forward from a stop into a turn. Turned out to be loose bolt in the suspension to the frame. Dealer checked all bolts for correct torque, found one that was loose and tightened it up. No problems since for 5000+ miles.

QUA77R0

Thanks alot Cabal_san.

I'll be taking it in to the dealer this week and mention this. Hopefully this will get it sorted.

snagitseven, I also had loose sub frame bolts. That was fixed last year. I had taken it in because there was a soft clicking /ticking sound at parking speeds while rolling forward or back. Seemed to go away or at least could no longer be heard once I started driving.

The clunk I was referring to is much more severe and does not happen until the brake is pressed firmly while in reverse.

av_audi

It's kind of unbelievable that we still get improperly torqued bolts connecting suspension components to the subframe. This problem seems to be more pronounced with VW/Audi for some reason, although that is just an impression I have, so it is not based on any data.

Art234

I currently have the problem with my 2010 A4 2.0t. It happens occasionally, but I notice it more frequently when backing while the wheels are turned...the clunk is quite pronounced and happened since the car was new.

The dealer service department is not that swift, but they did do the control arm replacement for the vibration issue last year after I insisted...

I am in the process of deciding whether to trade the A4 for the new A6 or the 535xi. I am having some driveability issues which remain unacceptable to me.

NickZag

The control arm bushings are definitely an Achilles heel of these cars, but I'm not sure how that would effect the brakes? It seems like you would hear the clunk all the time, especially when the wheels are turned.

QUA77R0

I don't think that it is the brakes per se. The clunk occurs when you hit the brakes but it does seem to be more like a suspension or driveline noise. I would expect to just hear it from the wheel well if it was the brakes. I am leaning towards it being a miss-sized bolt as Cabal_san mentioned. After the dealer retorqued the subframe bolts as well as redid the control arms, the clunk was baack by the time I got home (approx. 75 miles). I am really concerned that if it is a miss-sized bolt, that all this clunking is damaging whatever piece(s) are bolted together... ie. the mounting hole(s) may now be enlarged/elongated.

Waiting to hear back from Stasis regarding the nearest authorized dealer since I just moved and am clueless about SoCal.

QUA77R0

Finally got this resolved. Thank you Cabal_san for the tip and link. After visiting several dealers with the same complaint of the clunk when engaging reverse, finally one duplicated and fixed it.

R.O. states:

PERFORMED TEST DRIVE
VERIFIED CUSTOMERS CONCERN
PERFORMED INSPECTION
CHECKED SUSPENSION
INSTALLED CHASSIS EARS TO VEHICLE
FOUND NOISE COMING FROM LOWER REAR CONTROL ARM
FOUND INNER NUTS ON BOTH LOWER CONTROL ARMS TO HAVE COME LOOSE
REMOVED AND REPLACED BOTH NUTS
RETORQUED TO SPEC
RETEST DROVE VEH
VEH NOW OPERATING PROPERLY


It's crazy that something like this happens on our cars. I have had all the subframe and suspension bolts tightened/retorqued several times during 21k.

NickZag

Yikes... couldn't imagine that coming all the way off, especially as much as you track your car! Glad you found out the issue