Earlier this summer when I had the car loaded for vacation (no nivomats) the shudder in my drive train got much worse (on take off from standing). I recalled seeing a tip about raising or lowering the driveshaft centerbearing mount and figured if it got worse when the rear sagged, then I should raise the support. I just put a couple of washers between the mount and the mount plate and now its a lot smoother on take off.