Audi S6- Front End Clunk solved

[Roadwarrior]

My 2015 had a clunk in driver side front that would show up when backing down my drive and turning the wheels to avoid scraping (rather steep driveway).

The solution/problem was: The cross brace located under the plenum needed to have the bolts removed and then torqued to spec. The service manger told me they discovered this issue a while back. On S6s and RS7s, they previously had replaced control arms, and many other items trying to locate this problem- none of those were the culprits.. They said they have had 100% success with this simple fix they did to my car.

Since this appears to be a common problem, I thought I would share what worked for me and several others.

[IMG][/IMG]

[saxon]

Any pictures of the part your talking about?

[hmuller]

Cross brace makes me think of the part that would be replaced by the Alu Kreuz (once it finally ships).

[ntsantos]

Sounds like the little brace under the cowl? Very interested as I have the same sound. I thought it was the control arm.

[gk1]

Pics and location details please. Thanks.

[Roadwarrior]

Edit made- picture inserted on original post. Hope that helps.

[Ze_Nardo6]

Were the bolts not torqued to spec from factory? Or did they loosen over time?

[tenspeed]

Edit made- picture inserted on original post. Hope that helps.

I recently read a APR 4.0L down pipe install procedure that covered the removal and install of that part. I have the 3.0L and will never install down pipes but I thought it was interesting since it showed step by step instructions getting to that brace.

[Roadwarrior]

Apparently the brace can loosen. If it does and you get the "clunk" then you have to loosen all bolts and retighten. The APR instructions mentioned above are probably very helpful.

Reply back if this fix works for you. It would be nice to resolve this once and for all. Is it the same issue for everyone or can it be caused by multiple problems?

[gk1]

Edit made- picture inserted on original post. Hope that helps.

Thanks for the info. Very helpful.
Audi's official maintenance documentation term for that is the "Tower Brace".
There are 5 Bolts... torque specs are 20 Nm.

[ntsantos]

Just tried this. Backed out of the driveway and did a hot lap. So far so good. The true test will be in the morning, as that's when I usually hear the clunk the most. I'll report back in a few days to make sure it's not a placebo.

[wwhan]

The APR instructions mentioned above are probably very helpful....

"Remove the plastic pushclip and 10mm plastic nut holding the rain tray weatherstripping support. Remove the support from both sides of the bulkhead in front of the strut towers.

Install the stamped strut tower brace. Reinstall any attached brackets, and secure to the car with the five 10mm triple square bolts. Torque these bolts to 20Nm (177 in-lbs). Finally, install the two T25 screws holding the bulkhead to the strut brace.

Install the rain tray weatherstripping supports on both sides of the bulkhead. Secure with the the plastic pushclip and 10mm plastic nut."

[gk1]

I tried this as well since it was easy enough. BTW none of my bolts were loose. I think, as has been discussed, there are a couple of noise related issues at hand. The louder clunk, almost like a CV joint clunk, described here may be addressed by this fix, but the fainter rattle while going over bumps at low speed might still be lower ball joints as discovered in other threads since I still hear the faint low speed rattle coming from the front suspension. I'm sure I'll get it checked out one of these days.

[bander2586]

Gave it a shot this weekend and the knocking noise is gone. My bolts weren't excessively loose, but nonetheless still needed some tightening to spec. Thanks OP.....saved a second trip to the dealer.

[flyfishing]

I had this and was meaning to take it in. Then today I didn't see a speed hump and slammed on brakes and went over it faster than I wanted. Noise got louder. I figured it was this and the shop tightened it and noise has so far decreased. Shop said it was loose. Must be common issue.

[tenspeed]

I figured it was this and the shop tightened it and noise has so far decreased. Shop said it was loose. Must be common issue.

Which vendor will be first to come up with the bigger/stronger strut tower brace for the C7?

[parkstr8]

Mine was just in for service and I couldn't remember the fix...I told them control arms. ARGH! At least I can do it myself in 10 min.

[flyfishing]

I can confirm that this solved my problem. drove a lot more today. clunk from out of driveway and over other uneven surfaces gone.

For myself, usually I had a noise when turning more sharply and slowly over an uneven surface (driveway, dip in road etc). Noise gone now.

[ntsantos]

I tried the strut brace fix and it didn't help. But...I ended up finding a fix for my "clunk!"

I was digging through the cowl on the drivers side, and noticed I could replicate the noise by tapping on the black windshield washer reservoir. It turns out, the top portion of the reservoir would tap on the ecu. I added some sticky back felt to the bottom of the reservoir and GONE. So fuckin happy now

[aquarian]

Found this thread as I have been experiencing this clunking phenomenon lately from near the engine bay during low speed maneuvers that may involve twisting the chassis in my A7. Opened it up and started torquing those bolts to spec. To my surprise, all of them required 1/8 turn or a little more to be tightened to spec. I believe the center bolt required the most turning to spec. Hopefully this solves my problem.

[dudley123]

Going to try this on my 13'! I just picked the car up and all is well, except for the faint clunk in the morning backing out of my steep driveway. Excited if this is an easy fix.

[flyfishing]

Anyone got the original photo? Or know top of their head what socket size to use? Wanna show it to my friend with a clunk...


Sent from my iPhone using Audizine

[flyfishing]

Anyone got the original photo? Or know top of their head what socket size to use? Wanna show it to my friend with a clunk...


Sent from my iPhone using Audizine

[ntsantos]

After installing the 034 density control arms, ALL sounds went away. All sqeaks, creaks, clunks. Highly recommended.

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[OlyS6]

Anyone got the original photo? Or know top of their head what socket size to use? Wanna show it to my friend with a clunk...


Sent from my iPhone using Audizine

They are 5 separate 10mm triple square bolts holding the strut brae in place. I'm sure it's very common knowledge to folks that work on German cars, but I had no clue until recently and had an interesting time tracking down a triple-square set of sockets to be able to work on downpipes as well as sway bars...

[BCT]

Just had the dealer re-torque the "Tower Brace". I had a very bad "binding" sensation when turning at and past 90 degrees. Asked the dealer to address this and he looked at me like I was crazy....said this shouldn't affect anything. After the service there was a noticeable difference! Binding diminished and the steering seems tighter and more responsive.
The service manager said the bolts were a little loose.

[herbreal]

Sorry to revive this, do the c7 A6's have these brace? I'm having the same issue right after lowering my car (installed springs) and my mechanic couldn't locate the problem.

Thanks!

[OlyS6]

Sorry to revive this, do the c7 A6's have these brace? I'm having the same issue right after lowering my car (installed springs) and my mechanic couldn't locate the problem.

Thanks!

Yes. Simply open the hood and pop off the rain guard the base of the hood/back of the engine bay. You'll see a horizontal silver-colored brace that is held in place by 5 triple-square bolts.

[shoe3k]

This was my issue on my S6 as well at1200 miles on the clock. The bolts were not torqued to spec on the same part as you. I had an additional issue with vibrations in the dash and steering wheel and the bolt in the engine mount was loose as well.

[SlickMachine]

This solved most of the clunk noises on my A7, post-suspension install. I still have a small 'click'when I turn my wheels but I think that is tie rod ends.
What I did was loosen all 5 bolts, then Re-torque the two at each shock hat, then lastly the bolt at the firewall. I went with 40 ftlbs of torque because 20 felt too light to me, fwiw.


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[fusQer]

Did you guys also have the clunk sound when braking hard, whether at high or low speed? I have the clunk sound appear when reversing and turning the wheel, but also when braking hard. Been to the dealer about 5 times, they can't fix it. Replaced struts, upper control arm, re-torqued entire suspension, then they gave up. I took it to another dealership, they said must be the lower control arm, take it back to other dealership. They sort of suggested it may be the subframe. It's a 2013 A7 prestige with 81k miles.

[digdah]

You have no idea how many trips to the dealer it took without them figuring it out. In hind sight I got a motor mount and some worn bushings replaced. Frustrating for them to find out this was such a simple fix. Sad I didn't find this thread over a year ago.

[s4nicetry]

You have no idea how many trips to the dealer it took without them figuring it out. In hind sight I got a motor mount and some worn bushings replaced. Frustrating for them to find out this was such a simple fix. Sad I didn't find this thread over a year ago.

This thread should be stickied.

[smguest]

Just wanted to add my two cents and make it possible for others to find this solution. I had the same problem in my 2014 S6 but it seemed more of a popping noise so my initial internet searches did not find this thread. I took it to Audi and they had the car for a week, thought they found the problem (torn bushing) but it came back the next day. After discovering this thread, my son and I loosened and retorqued the strut bar bolts as described - problem solved. What a relief!

[flyfishing]

I have this noise again and need to retighten, but I did it years ago and forgot where to torque. Anyone have a picture again?

[LawDawg]

I have this noise again and need to retighten, but I did it years ago and forgot where to torque. Anyone have a picture again?

Here you go (circled in red; not my pic)

s6 strut tower brace.jpg

[flyfishing]

THANKS!

[Dasquade]

Just thinking, might be usefull to put some locktight on the bolts and torque them to specs...since it is a known issue they tend to get loose over time (depending on driving style i guess :p ).

[LawDawg]

Sadly, this was not the source of my new, post-sway-bar front-end clunk.

[hirzelch]

This solved the clunk noise on my 2012 A7. The noise was progressively getting worse so glad it was such and easy fix. I could see on the driver side where the brace had been sliding/shifting. Loosened all 5 bolts then torqued to spec and good as new. :)