Rear-end "Thump"

[dan_b]

Ok, so just exactly how many bushes are we talking here? I did the top mounts last week (see Steering Slop thread) and it would appear I need to get all the front suspension bushes done too to cure that vagueness!

Front suspension
Gearbox mounts
Rear diiff mounts
Rear suspension

How many bushes? How many hours do you think?

I'm not going to change the clutch, or the rear diff. Yet.

[porkkis]

I took a picture of the bush today. Here you can see that the bolt hole is not even nearly in the middle.
Part number should be also readable. It says "171 199 214 C \ D".

[s2driveruk]

blimey thats pretty off centre, though i think the mounting holes on the rear subframe are elongated so why does it make much difference?

[porkkis]

The question is are they elongated enough!

I guess that arrow should point to vehicle front(?). So the bush would be as in the image when looking from LH side of the car. Or should it point up?

[Jas11n]

I'm popping into my local specialists tomorrow,,,,will ask them what they think, though I'm 99% positive that mine was centred and not offset as in that pic

[ottawa coupe]

I took a picture of the bush today. Here you can see that the bolt hole is not even nearly in the middle.
Part number should be also readable. It says "171 199 214 C \ D".

that is the rabbit engine mount....or at least it looks like the rabbit engine mount that i put in my coupe. for the price i can't complain...yet. it was put in in the fall when i had MASSIVE clunking (basically all of the rubber had torn). i still have a bit of clunking but haven't looked at it because until a couple of weeks ago, it's been damned cold around here!!!! the coupe will be going under the knife soon as i can no longer look at my corrado just sitting in the garage!!!

i'll will soon be able to give a bit of a report as to how well it's survived the winter. i can't say wether or not it will be definitive because i know for a fact that one of the other diff mounts were installed incorrectly so i don't know what that effect is and i do have a craptacular "get it through the winter and deal with it in the spring so i don't care if it hangs correctly" rear muffler that may be hitting the rear suspension/driveline.

i intend to test each fix as they happen to discover the root cause of things and will report back!

[Graham]

I recently replaced mine for the powerflex jobbie and it has cured my thud, also the hole was definitely center

[Jamo]

I "used" to have this thump (very much worse in 1st to 2nd gear changes),,,. Before I wrecked the car I went down a couple of different routes.
First off I thought it was the rear box thumping somewhere, so replaced the rubber hangers for the OEM "chain enclosed in rubber" ones. Nope still there. I made the mistake of replacing the whole diffmount bush and bracket with an OEM one(more on this further on), but again the thump remained. I then bought the powerflex mount and this made the whole thing worse and I got a horrible vibration at 1500/2000 revs along with the mother of all drones coming from the back on the motorway at 70+ mph (not fun at all having to tootle along at 60/65mph) IMHO not a good mod if you don't ever track the car and need a bit of comfort on the motorway.
Then the crash happened,,,,,,whilst the car was in getting sorted, I've had the gearbox mounts replaced and also the rear wishbone bushes and subframe mounts done. Thump has now gone. I think it must be have been a conbination of all those that has sorted it,,,,,,no a very good answer, but seems to have worked in my case.
I still had the vibration and drone, so I removed the powerflex bush and replaced just the bush, "without" replacing the alloy bracket it's held in that Audi will sell you, telling you the bush isn't available on it own,,,,,,Rubbish!! it is!! part number 171 199 214 D. Check your family album for a list of what this bush fits to (I could list it here but it's as long as my arm)
All vibration and droning is now gone, no-more thump, and the gearchange has no shunt felt through the gear stick, change more precise and positive.

HTH in some way Dan

Bump just for you Fatty

[s2pete]

I replaced all three diff mounts! Powerflex main(hole in center) and both side mounts from audi! My shunt has vanished! Have noticed that prop shaft center mount might need doing next as it looks a bit baggy but I get no vibration!?? Might be worth checking this on your s2 bud!!