Has anyone ever heard of and know about torque converter shake. My car has had the motor and transmission mounts changed, front flex disk changed and the center support bearing apparently looks good. However, I get an intermittent shake that occurs around 2000 rpm 40 mph and seemingly right before the 2 to 3 gear shift. It varies in intensity, usually worse when applying a little more throttle.

Does the transmission in a 96 C280 have lockup? I believe it's a 722.4?