i just bought a 2000 a4 1.8t everything seems to be in order except two things.
the first, not a big issue, the abs light and e-brake light is on. rotors and pads were worn out i just replaced and now im checking codes tomorrow.

the second is my concern I get a big clunk when i disengage and engage the clutch when theres a load on it. It sounds like its coming from the rear diff. today i got the safety inspection and i got the mechanic to take a peak. he hoisted me up and i put it in gear and engaged the clutch. he said that it sounds like its coming from what i think he said was a cone shield that's attached to the rear diff so now im think u-joint?

So now some additional information i just bought the car 300kms and 3 days ago there was nothing and it all started coming on yesterday morning. The mounts are good, no movement in the driveshaft, small leak in the differential.Other then the clunk noise everything runs perfect.

tomorrow im going to get the rear diff fluid flushed. i am thinking of going to audi just to see if they have any known problems in this way and hopefully listen to it without charge.

Any ideas would be very grateful

 

Your clunk sounds like the rear diff bushings. It is a common thing for these cars. Look up "Stern power ring" for a solution. There are other companies that make stiffer bushings as well.

 

Thanks for that info it really helps, im in the same boat as the OP, its so hard to change gears smoothly on this car, every time i let go of the clutch i feel/hear a clunk coming from the rear, i had a my diff leaking and i thought that was the issue, after i fixed that i still had it, looks like ill try the stern power ring, thanks again.

 

Basically what happens is that the nose of the diff crashes into the body. The "Ring" takes up the extra slop in that front bushing.

Stern Power Ring and Stern Rear Diff Bushing Kit - Ringer Racing

 

yeah thanks man ill try this... sounds like a really simple install and a really simple fix

 

whats the difference between

Rear Crossmember/Differential Carrier, Billet, B4/B5 - 034Motorsport | Performance Parts for Audi, Porsche, and Volkswagen

and this

Rear Diff Mount, Poly, B4/B5 Chassis - 034Motorsport | Performance Parts for Audi, Porsche, and Volkswagen

and this?

Diff Carrier Mount Pair, Rear, Poly, B4/B5 Audi - 034Motorsport | Performance Parts for Audi, Porsche, and Volkswagen

 

there wouldnt happen to be a diy for the install of this?

 

Jones, the first link you have there is for the rear carrier for the diff. I don't know why this would need to be replaced. The second link is for the front mount on the diff (the same place the power ring would go, but rather than stiffen the bushing, it replaces the whole mount. The last link is for the bushings on the rear carrier for the diff.

There is a DIY somewhere....

 

so instead of buying the crazy expensive albeit sexy mounts. you can buy a stern power ring and the bushing I posted and it should be stiff.

 

The ring is just a piece of aluminum that fills in one of the voids in the stock bushing. The other one replaces the stock mount and bushing all together.