driveshaft vibration problem

**Mister2** · 01-09-2009 04:47 PM

I'm having an issue with my drive shaft. The noise and vibration is coming from the rear end, sounds like under the rear seat area. It sounds like something has come loose and its touching the drive shaft. The noise/vibration happens whether its in gear or not, as long as I push the gas it will start up. But as long as there is no load on the drive shaft its silent. It started doing it a few weeks ago, mostly noticed it only if I made a sharp turn to the left or if it was raining. But over the past 3 days it's gotten significantly worse and its pretty loud. Almost sounds like the u-joint is hitting something solid.

Has any one had a problem like this? Any help would be greatly appreciated! I'll try to keep an eye on this thread and answer any questions. My friend has offered to let me use his garage this weekend while I'm off work so hopefully I can get this resolved.

I tried a search and didn't come up with anything, I was told it was probably the u joint so that's what I've been focusing on.

**B5A4Kevin** · 01-09-2009 06:14 PM

have you recently had the trans out, or done a tailshaft seal. if so, the driveshaft may be misaligned, throwing it out of balance.

**Mister2** · 01-09-2009 06:16 PM

no, the only tranny work i had done was when i had my new clutch put in, and that was last winter if i remember correctly.

**bikerbob951** · 01-12-2009 10:26 AM

bump, cause he needs it

**djwimbo** · 01-12-2009 11:14 AM

For starters we don't use U-Joints. We have a CV-Joint at both ends of the driveshaft. I found out first hand what happens if a bolt isn't tightened down and falls out, or for some odd reason somebody loses a driveshaft flange bolt.
This will cause a serious vibration and noise before 35mph, and you won't even think about driving the car until the problem is fixed, so it makes me think that's not the issue in this case.

Have you checked the splash guards that run under the driveshaft? I've seen a couple times where a customer had some issues with that rubbing after hitting a large puddle or pile of snow.

Does it seem like there's a lot of play or slop in the rear upon acceleration? It's possible you have a junk bushing/mount at the front of the differential. That would probably be more pronounced as a clunk when going from accel to decel, or on engine braking.

**J Ozzie** · 01-12-2009 11:20 AM

ive had that sound as well but its only after hitting a puddle or deep slush...

**andyrew** · 01-12-2009 11:32 AM

Originally Posted by djwimbo

For starters we don't use U-Joints. We have a CV-Joint at both ends of the driveshaft. .

And we have a U joint (or whatever that thing is) in the middle of the drive shaft halfs...

**djwimbo** · 01-12-2009 12:38 PM

Originally Posted by andyrew

And we have a U joint (or whatever that thing is) in the middle of the drive shaft halfs...

ok, true, but the likelihood of that being a failure point is very very low. Given that the noise is coming from the rear, I wanted to clarify that there wasn't a U-joint back there.

But yes, you are correct, there is one U-Joint in there. It's there so that the driveshaft has more flex(angle from driveline "slop") and is easier to remove.

**nunya** · 01-12-2009 01:14 PM

It could be a diff mount gone bad.

--dillon

**SpoolinPelican** · 01-12-2009 04:14 PM

Are you sure it's not the exhaust rattling around?

**Mister2** · 01-12-2009 06:38 PM

Originally Posted by djwimbo

For starters we don't use U-Joints. We have a CV-Joint at both ends of the driveshaft. I found out first hand what happens if a bolt isn't tightened down and falls out, or for some odd reason somebody loses a driveshaft flange bolt.
This will cause a serious vibration and noise before 35mph, and you won't even think about driving the car until the problem is fixed, so it makes me think that's not the issue in this case.

Have you checked the splash guards that run under the driveshaft? I've seen a couple times where a customer had some issues with that rubbing after hitting a large puddle or pile of snow.

Does it seem like there's a lot of play or slop in the rear upon acceleration? It's possible you have a junk bushing/mount at the front of the differential. That would probably be more pronounced as a clunk when going from accel to decel, or on engine braking.

I didn't really get a chance to check much. I got under the car but wasnt able to see much because I couldn't get it high enough. The jack even broke. Nothing really jumped out at me as being obviously broken. I don't see how I could inspect much of it without completely dropping the exhaust and removing the heat shield above it. The rear doesn't really seem to have any slop, or any more than normal.

**Mister2** · 01-12-2009 06:39 PM

Originally Posted by SpoolinPelican

Are you sure it's not the exhaust rattling around?

I know its not that because my exhaust is rattling and its a different sound all together. I did however find out where the exhaust is hitting. The sound I'm more worried about is much louder and directly related to RPM's