Driveshaft ping journey (6MT)

[Bubbles]

Driveshaft would ping under load, upon quick throttle release, and when changing directions (going into reverse). I first noticed the noise during a sloppy downshift at the track (around 50k), the noise didn’t seem to get louder but was easier to replicate.

After several track days and another 20k, I decided to chase the noise by changing out the Guibo/flex disc with new bolts. Center bearing looked ok and cv joint seemed to be in good shaft.

Result: Driveshaft felt better but the noise remained.

At 80k, left rear half shaft was causing problems (cv joint no longer released smoothly). While the car was on the lift for the half shaft repair, I replaced the driveshaft cv joint with redline grease (bought a bmw cv joint on clearance for $100). Center bearing looked ok and didn’t show significant play.

Result: car smoothed out (load and unload) but the noise remained albeit somewhat muted.

Yesterday, I found a center bearing on my parts shelf and decided to install it. I used a hydraulic press to remove the old one (WD40 is key), it came off easily. I did noticed the old center bearing seemed to be flaking off the outer layer of rubber.

Prior to installing the new center bearing, I cleaned the splines with WD40 and used castrol optitemp 2 to grease the splines. I was surprised the splines were bone dry. Installation of the new center bearing took almost no effort, I expected to use a 36mm deep socket to mount but I didn’t have to use it to get the center bearing seated. Although I had two new shims (I must have ordered it twice) I noticed the old shim was .02mm thicker than two new shims so I cleaned and reinstalled the old shim (new bolt and washer). Installed the driveshaft and preloaded the center bearing.

Result: Noise is gone and the driveshaft feels great, loading and unloading the driveshaft is very smooth. The u joint is in good shape but I’ll know soon enough. Deansbimmer mentioned this noise is overall driveshaft slop, which makes sense.

In hindsight, I would buy a new driveshaft and save the time.

[bvrider1]

Nice job! Thank you for sharing.