Transmission --> Driveline issues

[SwiftE30]

Revshift flex disc
OEM e30 drive line
S52 and zf transmission
New CSB
UUC e36 trans mounts w/reinforcement cups
E28 engine mounts
U-joints are fine
Driveline marked and matched correctly when reinstalled

Installed everything and went for a drive and completely tore apart my CSB. There was an extremely loud banging when I drove it so I pulled it back into the garage and then noticed the CSB. Replaced it and made sure everything was tightened down. The car is up on stands so I can watch the driveline while the car is in first with back tires spinning. The driveline at the CSB is spinning roughly half inch out of true.

Read how a few guys shim their trans so I took off the reinforcement cups to see if that was causing the bad alignment. Seemed like it made it a little better but the car is in no way drivable.

Any suggestions? With the amount of how untrue my driveline is, there has to be something completely wrong. I'm thinking my trans is still sitting at the wrong angle and I need to loosen my engine mount bolts so the trans can sag down more to match up the the crossmember better.

[jlevie]

Bobble in the drive shaft like you are seeing will usually be from binding u-joints in the drive shaft.

[SwiftE30]

all the U-bolts checked out fine, and there was zero problems with them before the swap. Now that I'm thinking about it, i never loosened the flex disc bolts so the first half of the DL didn't have a chance to readjust after removing the reinforcement cups on the trans mounts. They added a strong 1/4" to the height to the trans mounts making them bigger then the OEM ones.

I think if i loosen the engine mounts and flex disc bolts andf then mount the trans crossmember again this will allow it to be at the correct angle.

ANyone have any thoughts on this?

[jlevie]

I doubt that fiddling with the guibo is going to do any good.

If you are certain that the u-joints are good, then I'd suspect a misalignment of the engine and the rest of the drive train. That could be from wrong motor or transmission mounts or the wrong transmission crossmember. You might be able to tell if that is the case by unbolting the guibo and looking to see if the output flange and guibo meet at an angle.

[SwiftE30]

I am leaning towards misalignment. I think that the reinforcement cups are he root of the problem. Having those installed and then tightening everything down cause the transmission to sit too high at the crossmember. When I took off the cups and tried to reinstall the crossmemeber the trans had to be pulled down to match up to it. i didnt have to support the trans at all, it was just staying up high. LEading me to think the angle is way off.

[samstrimbu]

if you changed the motor mounts out and they didn't have the little aligning pin in the then your motor could be misaligned and causing the problem. had that problem when i helped my brother swap a s50 into his e30 m3. the motor mounts misaligned the whole drive train and was causing a very similar problem. take the old ones out and by ones with the pin on them will save you a bunch of time and fix the problem.