I have a 1989 740 turbo sedan, with a manual transmission and overdrive. The car has a bad shake when starting out in first which is worse if a heavy load is placed on the car. I have checked the drive shaft, flex plate and center carrier bearing all appear to be in good shape. I see the trans sits low so want to replace the trans mount as next possible problem spot.

Here is my dilemma, ever parts house including the dealer tells me I should have a round mount, but the car has a square mount like the automatics have. The cross brace fits this square mount and the trans has a stud which appears to corresponds with that type of mount. Any Idea why this would be?

 

I have seen both too but typical set up on a 740 is a square mount for manual and square for automatic...there are 2 different types of square mounts one is short and one is long...doesn't matter as long as it fits correctly(make sure you match yours up). But if you have a bad shake usually the motor mounts are bad...not just tranny mount...check motor mounts too.