driveline noise on hard acceleration...

[rsfeller]

I'm troubleshooting the brother-n-laws 04 Twin Turbo from long distance, I won't see the car until later this week.

He claims he was able to reproduce twice when he really got on it some bad vibration (feels like the center of the vehicle). He actually thought he blew a tire or lost a wheel the first time. He got out to look and saw no concern...then got in the car and it drove fine until he gave it an agressive acceleration...he said about the time the turbos fired he got the crazy vibration a 2nd time. Again normal driving he had no perceived concern.

I've been doing some reading and lots of drive shaft failures before 50K miles, I think he's got about 80K.

Does this sound like a failed driveshaft? The only time I had a bad prop shaft on a BMW it had a old vibration at many speeds...but I'm sure the failure trend was different.

Edited May 29, 2011 by rsfeller

[wvicary]

Sounds like the driveshaft to me.... it will get worse quickly. I have read many post with people getting the centre brng replaced with some success and then having vibration problems after due to a balance issue. I would just get the updated part from the dealer network and be done with it.

[rsfeller]

Sounds like the driveshaft to me.... it will get worse quickly. I have read many post with people getting the centre brng replaced with some success and then having vibration problems after due to a balance issue. I would just get the updated part from the dealer network and be done with it.

Thanks. So the center bearing and shaft are different failures to this concern? Is the balance issue to to the bearing or something else being off in the shaft? I see some of the aftermarket shafts are balanced.

I guess I'm curious what will happen to him when this finally goes since he says he needs to drive it to work this week. Does this depend on the carrier bearing being the failure point or do the C/V at the diffs fail too and snap?

Edited May 30, 2011 by rsfeller

[mudman2]

when is goes he wont be going to work

[rsfeller]

when is goes he wont be going to work

I get your point but not very useful to my understanding...could you explain the failure trend? I'm not getting from the other posts on this topic what truly fails.

He's down on his luck due to the economy so I'll most likely be doing the fix but won't see the vehicle to Wednesday, since he says it drives fine as long as he doesn't get on it and we are not 100% sure of the cause...I know he'll push the envelope since he has no option right now.

Again is it the carrier that fails and causes the vibration from it's travel or is more to do with C/V failure which is what I have seen on other 4x4.

Thanks.

[wvicary]

Sounds like the driveshaft to me.... it will get worse quickly. I have read many post with people getting the centre brng replaced with some success and then having vibration problems after due to a balance issue. I would just get the updated part from the dealer network and be done with it.

Thanks. So the center bearing and shaft are different failures to this concern? Is the balance issue to to the bearing or something else being off in the shaft? I see some of the aftermarket shafts are balanced.

I guess I'm curious what will happen to him when this finally goes since he says he needs to drive it to work this week. Does this depend on the carrier bearing being the failure point or do the C/V at the diffs fail too and snap?

It's the centre brng rubber carries that fails and cause the driveshaft to float around. I've been told it's a one piece shaft and doesn't come apart unless it's cut apart. I don't know if this it true but I have looked at a failed shaft and I couldn't see anyway to seperate the two halves. i would not recommend driving the vehicle in this condition as it could damage other things. I have never seen or heard of any other problems with the drive shafts/axle on the Cayenne other then this issue.

[rsfeller]

I did see one guys post about only replacing the carrier bearing...so my next question was in fact if the carrier bearing can be separated from the shaft. Is this what you are stating from your understanding is the carrier doesn't come off w/o cutting up the shaft as the ends are most likely in the way. I'm trying to find a photo online as we write...

I also see a company out of colorado who makes a HD replacement...so I'm guessing this is needed for CV failures?

Thanks for your patience...it's hard for me to troubleshoot this for him until I can see the vehicle.

[rsfeller]

OK, didn't see this thread the first search around:

all my answers are there!

[rsfeller]

Gang...

See this post for reference:

The last post the owner talks about just finding a replacement for the carrier bearing for a lot cheaper...and it appears they then balanced it to for a far cheaper price. What are you thoughts?

Since it's not my car and the person who owns it is financially in a rough spot...anything is worth a try even if it only lasts a few years.