BimmerFest BMW Forum banner

Z3 rear diff mount issues

4K views 6 replies 4 participants last post by  TBuff 
#1 ·
I am currently building a 99 Z3 for the wife. The car was given to me as payment for some work did for the owner. The issue is the car was in a wreck, it was hit on the driver side rear quarter. I found a parts car for cheap and have most of what I need to fix the car. I will be swapping the rear diff assembly from the parts car as the lower control arm on mine was bent. I have both assemblies out and the diff I will be installing at the local BMW shop being inspected before installation.

The big question I have is the diff mount is starting to split. The only place splitting is where the third member bolts to the body, I do not see any other stress cracks in the body. I understand this is a common issue and there are kits out there to reinforce this area. Can anybody suggest a good kit to go with? I've looked at several sites and not found anything as of yet, I think UUC makes one?

The original diff had 3:15 gears in it and the new rear has 4:10 gears since it was an auto. It should make for a fun car to drive when I is done! Thanks in advance for the info.
 
#2 ·
I'm not up on rear axle ratios, but 4.10 sounds like it could be from a 4 cylinder car. I would wonder about the strength of that differential for a 6 cylinder car...Randy Forbes, who visits these pages regularly is the guy to answer your differential mount question
 
#3 ·
#6 ·
#7 ·
I've been in contact with Randy. That is a very nice kit he offers. I already have the rear of the care completely stripped so no "real" extra work to install it. :eek:

I am not really concerned with the extra RPMs or loss of milage. This will be a weekend toy to enjoy instead of a daily driver. She is excited about having some spirited 0 to 60 fun or enjoying a spin down the Blue Ridge Parkway.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top