When starting from first gear, or even second gear, the car shakes pretty violantly. I'm not sure if its the clutch or the rear. I finally got ride of the noises in the rear end when I added the additive for the posi unit but this problem was there before that. It seems to have gotten worse. The clutch and pressure plate are brand new. I just installed a 2" drop disc brake kit and also lowered the rear. I have not been able to really troubleshoot the problem yet and was looking for some pointers. Is it possible that the rear is binding? What and where should I start? I'm new to four speeds and posies. It only happens when starting from a stop and shifts fine when rolling down the road. :confused:

It only happens when starting from a stop and shifts fine first thing i would check is make sure you dont have a broken motor mount,it'll give you the same type of "shudder" your talking about. jeff

it sounds like it could be the pilot bushing or throw out bearing. Also, did you resurface the flywheel when putting in the new clutch?

Had the same problem a few times. found these fixes,

- motor mount or transmission mount
- did not resurface the flywheel with new clutch assy.

possibly check the flywheel if it is externally balanced or internally balanced..must match the engine..i had the same problem then solved it with t
he flywheel