Thunk from rear going over potholes or bumps

[Slabber]

Every time I go over a pothole or a bump in the road I hear/sense a 'thunk' from behind me. My garage have given the suspension a thorough going over and can't find anything wrong. The exhaust seems to be firmly in place. Anything else they could check?

[ainarssems]

Rear diff bushes and check if the spare wheel is secured in the boot or any other loose items in boot / spare wheel well.

[Slabber]

Thanks for that! Spare tyre is definitely secure but rear diff bushes sounds like something that may not have been checked.

[Slabber]

Okay, my garage (Audi independent specialist) have now given my car a thorough inspection and can't find anything wrong with the suspension, nor with anything else that might be causing the 'thunk' from the rear. They can hear the thunk though, which is something I suppose. I'm now considering having some rear suspension parts replaced on a speculative basis. Grateful for suggestions as to what to start with!

[Slabber]

Update to help someone else in the future.

I finally had my garage do an in-depth investigation in to my suspension 'thunk' and it turned out that a new air suspension strut that was fitted last year was faulty: when they took it off (which is a massive job BTW) there was something loose inside. Luckily it was under warranty and even better the manufacturer was happy to accept the warranty claim via a video of the strut making a noise rather than having to ship it to Germany for inspection. New part now fitted and the thunk gone!

[Joe2.0E]

Glad you got sorted at last.
Was the faulty strut a genuine part or aftermarket ?

[H-M3]

Might be useful for us if you can upload the video of faulty parts

[Slabber]

Originally Posted by Joe2.0E

Was the faulty strut a genuine part or aftermarket ?

Aftermarket. I didn't mention the supplier as I'm not 100% certain (my garage handled everything), although I'm pretty sure there is only one major supplier of aftermarket air suspension parts in Germany. Aftermarket doesn't necessarily mean cheap though: still £550+.

[Slabber]

Originally Posted by H-M3

Might be useful for us if you can upload the video of faulty parts

I'll check if my garage are happy for me to post it.

[Slabber]

Here's the video! Nothing to see per se - just the noise coming from the strut.