Diff Issue

[Spartyfan99]

Hey guys. Just picked up a 1989 325i coupe a couple weeks ago. Everything seemed good until i noticed a clunking in low speeds, especially while going over a bump or turning. I jacked up the rear and checked it out. If i turn a wheel back and forth somewhat rapidly i notice the clunking. I think it is the ring and pinion just worn out? not to sure. It is an LSD, not sure on ratio as it has had a lot of swaps for track use. Any help or advice would be appreciated. Thanks guys.

[redlightpete]

There are a lot of clunking opportunities with a worn e30. Some amount of drivetrain slop is normal. It could be the half shafts, diff, drive shaft, or trans. The half shafts and drive shaft should be pretty slop free, and the ring and pinion free play is specified (BMW TIS). Get someone to create the clunking while you're under the car feeling for contributors. If your car has all the heat shields in place you won't be able to get to the center drive shaft u-joint without removing the exhaust, but you may be able to hold both ends and feel if there is any relative movement.

[Spartyfan99]

There are a lot of clunking opportunities with a worn e30. Some amount of drivetrain slop is normal. It could be the half shafts, diff, drive shaft, or trans. The half shafts and drive shaft should be pretty slop free, and the ring and pinion free play is specified (BMW TIS). Get someone to create the clunking while you're under the car feeling for contributors. If your car has all the heat shields in place you won't be able to get to the center drive shaft u-joint without removing the exhaust, but you may be able to hold both ends and feel if there is any relative movement.

Thx, I think I have narrowed it down to the drivers side half shaft