just picked up an 84 190D [Manual] - it sounds and feels like the Universal joint under my feet is bumping upward against the floorboard when applying torque in 1st and 2nd, but smooths out into 3rd and on...

i'm told that a bad (rear) transmission mount(s?) would allow this to happen - does this make any sense?

thanks for your expertise and help...

regards,
Glenn Nall