designin

My '09 4.2 TDI has developed a transmission grumble. I believe that I've traced this to the centre bearing of the prop'shaft. When I push up and down on the prop'shaft I can hear a metallic 'ting ting' from the bearing area (it's up behind the exhaust and an exhaust heat shield and so not visible). The noise is more pronounced when I push on the rear section of the shaft so it could be the universal joint that is just behind the centre bearing. As far as Audi is concerned the prop'shaft is a non serviceable part and must be replaced in it's entirety; which is very expensive.

New centre bearing + support units are available from third party suppliers. Getting the shaft out doesn't appear too difficult, does anybody have any advice on splitting the shaft so that the centre bearing can be replaced ?

the_duke

I haven't read about this issues with the D3's but it's a reasonably common problem on A6 C5's. Unfortunately the best option is probably a new or used drive line. As it's not common you most likely won't find a company that refurbishes them.

richard-tx

A center bearing change is a royal PITA on a D2. To make matters worse, the driveshaft is made from carbon fiber so clamping it in a vise could destroy it. The wrench needed to split the driveshaft is a special one. You best bet is to get a used or new driveshaft and replace it as an assembly.

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dvs_dave

The prop shaft on a D2 is carbon fiber....really? All of them or just the S8? That's very exotic.

What about the D3? Not heard about any carbon driveline parts.

richard-tx

It was a D2 driveshaft that was carbon fiber. You will know for sure when you take it out, If it is light, then it is likely carbon fiber.

designin

Thanks for the replies, It's a steel prop'shaft in my D3. The price of a new one is £1,426 ($1,800) but I think that this is the way to go. I've just had another look underneath to check which exhaust gaskets etc. I should be renewing and I'm now fairly certain that it's the CV joint that is the problem. When I grab both halves of the prop'shaft and move them in opposite directions I can get a very small movement both in rotation and longitudinally. The centre bearing can't contribute to this movement.

designin

FYI it is possible to get a new prop'shaft for the long wheelbase A8 D3 from GKN under their Spidan brand, start here GKN - WEB CATALOG and you should end up with their model 28118, or 28128 for the 4.2 FSI, I have seen this priced at half the Audi price. Unfortunately for me they don't offer a prop'shaft for the standard wheelbase car. The 28118 is 1,868 mm long, the shaft on my car, including the CV joints at each end is about 1,735 mm + a bit in the cupped flanges which makes sense as the difference in wheel base between the standard chassis and the L is 130 mm. Other than the 4.2 FSI they don't differentiate between the standard and long bodies, they also list the 28118 for the S8 but since the S8 was only built in the standard wheelbase I think that this is a mistake.