endless_corners

I can wiggle my driveshaft with my hand and thus will need to replace the center support bearing/bracket. So far options seem like either replacing the driveshaft with a rebuilt/new unit or refurbing my existing shaft. I found this product last night while googling and have only found some chatter re: installs from the touareg crowd. It allows you to install a new bracket without dropping the drive shaft. What do y'all think?

here is a product link

endless_corners

I found these touareg links...

http://www.clubtouareg.com/forums/f9...t-61828-2.html

https://sites.google.com/site/vwtouaregdriveshaft/

medtech

I've had it on mine for over 6K miles now, and I like it.

The pros: it goes on easy, you don't have to replace the driveshaft, and there's no re-balancing needed.

The cons: since it's a "floating" design it allows a little more vibration of the driveshaft than the original rigid design.

If you order it, you will also need to order a replacement gasket for the front end of the shaft (I forget the exact name of the part).

Theoretically a car's driveshaft should last between 160K to the life of the car. With the EPS support you won't need to replace the shaft over and over again (BTW, those little red/blue arms are individually replaceable should they wear out).

Hope that helps.

endless_corners

thanks for the replay med.. One followup question:

How does this gasket relate to the bracket retrofit? I'm trying to visualize what you mean here.

medtech

^^
It doesn't relate to the bracket itself at all.

It is a large rubber doughnut that goes onto the forward end of the shaft where it attaches to the tranny. It is usually worn or damaged when the OEM bearing support dies.

Vertex sells it, but I'm not sure they make it clear what it is or why you need it when you order online.

endless_corners

I'm gonna hop under the pig and check that area. Does the drive shaft have to be disconnected to put it on?

deilenberger

In BMW talk - that's a "GUIBO" (aka flex-coupling).. and I'd suggest OE for this part, some "OEM" and aftermarket ones have been known to be very short lived in the BMW world.

deilenberger

Yes. And at that point, it becomes a moot point if simply replacing the driveshaft with a rebuilt one from Vertex is a better idea (it's a cheaper idea if you're DIYing the job.) I believe the rebuilt ones from Vertex come with a new flex coupling.

deilenberger

Not so easy if you're replacing the flex-coupling at the same time. And I do recall a writeup from someone who installed one who had a real problem getting the rubber from the old coupling off the bearing.?? The original design is anything but "rigid" - the flexible part that allows the bearing to move around a bit is what goes bad.While that may be theory, in reality - failure of a driveshaft after 80,000 miles or so isn't "unexpected". The big problem with this device I see is it doesn't replace the bearing, and there is an excellent chance a bearing going bad is what causes the rubber mount to self-destruct. The fact that you get "more vibration" might indicate that you do have a bearing starting to go bad. Or it may indicate that the mount is too rigid. In either case - I don't see more vibration as being a good thing.

Having to replace the front flex coupling means you're disconnecting the front end of the driveshaft anyway. Combine that with taking the bearing mount down, and you're 2/3rds of the way to replacing the entire shaft.

The same vendor who makes this item (or at least sells it) Vertex also sells rebuilt driveshafts, for considerably less money then just this mount. People have reported installing a driveshaft in 30 minutes or less, and that was on jackstands. On a lift, it's likely to be even easier and faster. The only problem anyone reported replacing the shaft is disconnecting the rear coupling from the rear differential input. Apparently that's a tight fit that can lock itself on, but using some pullers it appears people have gotten it off without too much difficulty.

Just my opinion, but I see no real advantage to this mount vs replacing the shaft itself. There are vendors who will sell you rebuilt/rebalanced shafts, but I really doubt if the balance is changed by just replacing the center bearing (I can see no reason that it should be, as long as the shaft isn't dropped or bent doing the job. It's a pretty healthy chunk of metal, not likely to go out of balance) and I can't recall seeing complaints about balance/vibration after replacing the shaft with a rebuilt. One or two vendors also offer an "improved" center bearing design with their rebuilt shaft - wider bearing with a thicker rubber mount.

Just my opinion.. if it was me, I'd go for the rebuilt shaft.

medtech

All you have to do is unbolt it, put the new "flex-coupling" on and re-bolt. No need to re-balance or do anything else.

endless_corners

I talked to someone at vertex today. I was told the reason for needing to replace the flex disc is because its made of a rubber material that hardens. This causes more stress to fall on the center support bracket and is the leading cause of failure. He said that bearing failure is not common. So... I'm pretty much sold on the updated clamp and new flex disc vs a rebuilt driveshaft because I can do it all myself. Once the fix requires dropping the exhaust it's going to my Indy and going to get more expensive. In a way though it seems like the best of all worlds solution would a rebuilt shaft + the updated center support bracket. But I have to wonder if I will keep this cayenne past another 100k miles since I am averaging 5-10k / year.

Btw thanks for all the input fellas.. Appreciated.

Km1.8t

You do not need to drop the exhaust. But you do have to remove a couple of clamps and seperate the pipes so that it makes some room to get the shaft out from under the car. I have replaced the the shaft in the garage with a couple of jack stands.

Orantes

You can hear a failed bearing. Tweets like a bird.

Orantes

Sorry, I know this because my centre bearing failed at the same time the rubber around it totally disintergrated. I believe that these two occurrences were related.

bigbuzuki

^+1 on the tweeting.

Mine also did the "tweeting" for a little as the bearing was failing.

Then the tweeting morphed into a thumping sound.

It sounds like a midget with a under the floor as you accelerate.