Is there any better way of doing this than just guessing and replacing random parts? My Audi has a vibration when the drivetrain is under load at around 60-80mph. It has been to Audi twice now and they have spent 2 weeks and the best part of £1k of my money looking at it and running it up on the ramp to 70mph to see where is vibrating.

This time say that they could see the rear diff vibrating and have done a couple of things to the diff/prop/rear driveshaft which they are confident has 90% cured the problem. To 100% cure it they list a new diff at around £2k and new driveshafts at £200 each (all plus VAT). At first it did feel better but now i'm not sure (the problem is only really obvious on the motorway when you are constantly around these speeds)

I am confident that the problem feels like it is coming from the front end and as the steering wheel stays still it is a driveshaft or front diff problem. But I don't want to throw money at new parts that aren't needed! Is there any better way of telling what is wrong?

 

All i can suggest is ring round audi specialists to see if they have any advice, Audi quattros are fairly rare so might not be the sort of thing your local audi dealer sees in, where as a specialist who only works on s4's/s6's can probably offer further advice.

 

i woul disconenet the 4wd and but it on the dyno and see if it still does it
and go from there

 

Thanks guys I have done a quick search and have a few Audi specialists to call. Does anyone know of any that they have experienced?

 

have you tried rs246.co.uk? i know theres a couple of chaps on there that people swear buy.