Driveshaft (Drive shaft) Failure?

[lividfanatica]

I had my car in for an alignment a couple of days ago and the guy that worked on my car noticed the "clunk and squeak" that i have had for a few months. I thought it was differential mounts, so i bought a set and have been planning to replace them one of these weekends. He tells me it is the drive shaft... not the CSB and not the Diff mounts.

I am hoping to tear off the exhaust and figure out exactly what it is but is a U Joint failure on the drive shaft common on these cars? I barely see any posts about drive shaft problems on stock ZHP's.

To offer more of a description... the clunk occurs the most in stop and go traffic when i am in a low gear, giving a little throttle then letting the throttle up without clutching.

My baby is an 03 ZHP - 6 speed.

[ELCID86]

Welcome. Sorry for your woes. I'm sure others here can help. Possible Guibo? http://www.zhpmafia.com/forums/showthread.php?10146-Rumble-Under-Hard-Acceleration-(e46-M3)&highlight=guibo

[LivesNearCostco]

Yes the U-joint can fail but it's far more common for the guibo, CSB, transmission mount, motor mount, and/or rear (big) diff mount to fail. (FCABs and RTABs aso fail but they are much less likely to cause a thunk under acceleration.) The diff mounts and transmission mounts can be seen pretty easily from under the car. The motor mounts can be analyzed from above (look for leaking oil on OEM mounts) or below if you remove the plastic shield and gently lift the engine. Part of the guibo can be seen from below but IIRC it's impossible to see the CSB or driveshaft U-joint unless you remove the exhaust and some heat shielding.

So either your mechanic has a lot of experience diagnosing BMW driveshaft problems by sound alone or he saw something that made him think U-joint. Or he's just fishing for more paid hours from you!

If you said only thunk upon accel/decel in low gear, I'd say it's definitely diff mount or left motor mount, or possibly subframe bushings. But clunk and a squeal? I dunno... Have you looked at your diff mount and seen cracks? Have you looked at the transmission or motor mounts? Did your mechanic say how he knows it's the driveshaft and which part of it? After all the driveshaft connects to the guibo and spins inside the CSB. How many miles on the car?

[lividfanatica]

152000 on the car. The sound is definitely coming from the rear of the car, you can feel it on your bum when you sit in the back seat. I have replaced RTAB's and FCAB's. The squeak is like metal rubbing on metal. My friend swore it was a diff mount.. but from what i can see they all look good and i cant move the diff by hand. Glad to hear it isnt common... i will update you guys when i tear it apart and hopefully find my answer.

CSB makes sense to me if the shaft is rubbing/banging on it when i release the clutch. Hmmmmmmm....

[Lanister]

Csb will cause clunk and vibration under acceleration. Guibo might be worn too. The mileage is pretty high. What wears out the guibo is aged tranny mounts, which make the tranny sag.

Sent from outer space...

[Smolck]

152000 on the car. The sound is definitely coming from the rear of the car, you can feel it on your bum when you sit in the back seat. I have replaced RTAB's and FCAB's. The squeak is like metal rubbing on metal.

Lots of guys forget the upper and lower rear trailing arm bushings when they do the RTABS. Videos of the process reside on my youtube page.

A more common failure is the springs.

[LivesNearCostco]

Smolck, I did forget these when I had my RTABs done (over 2 years ago), now I've purchased the replacement bushings (6 bushings, 2 ball joints) and planning to replace them when I do the diff bushings. Did you replace your lower outer RTA bushings with a ball joint, which I hear is the way the E46 M3 trailing arm is set up? Do you know what the benefit is of changing that bushing to a ball joint?

The rear upper control arms intimidate me, but I'll check out your videos and maybe that will inspire me to DIY it.

[Smolck]

Smolck, I did forget these when I had my RTABs done (over 2 years ago), now I've purchased the replacement bushings (6 bushings, 2 ball joints) and planning to replace them when I do the diff bushings. Did you replace your lower outer RTA bushings with a ball joint, which I hear is the way the E46 M3 trailing arm is set up? Do you know what the benefit is of changing that bushing to a ball joint?

The rear upper control arms intimidate me, but I'll check out your videos and maybe that will inspire me to DIY it.


Don't let them make you fear, they are easy.

I did go with the ball joints all around. It is a better feel because no more rubber.

[lividfanatica]

Lots of guys forget the upper and lower rear trailing arm bushings when they do the RTABS. Videos of the process reside on my youtube page.

A more common failure is the springs.

We did do the lower RTAB (replaced with ball joint) it was a little challenging to get it out. The uppers looked good so I left them alone. How can you diagnose a bad spring? They look normal to me lol.

We found the source of my clunk - Started by looking at the Guibo, it looked pretty good. Then we jacked up the rear end of the car disengaged the parking brake and left the car in gear. Then we turned the rear wheels back and forth and very quickly saw a lot of play in the rear differential bushing but no play in the guibo. I paid a shop to do all the diff bushings as well as all new diff seals and new fluid. Cost about $575 in labor after tax (i already had most of the parts).

[ELCID86]

Glad you got is sorted out. Driving smoothly now I assume.

[lividfanatica]

Yes, everything is great! I wish i had time to try and do it myself, but at any rate I am glad it is fixed. Thanks to everyone for the suggestions!