I just paid 900$ to have a used tranny put in my 2000 volvo s70.
It still shifts hard from 3rd to 4th gear. Any suggestions as to what to check next? The previous tranny still moved but not all the time and would stop working after a few minutes. Any suggestions, please? 200,000+ miles on the car, 140k on the new tranny.

 

did you drain all the old fluid with the install? if not try a drain fill making sure you use the right ATF fluid and consider a synthetic. Double check the fluid level cold and warm. Only other things I can think of is maybe your transmission cooler is not working efficiently allowing the transmission to over heat or you just got a tired replacement transmission.

 

I would change the transmission fluid and see if that helps. Also check out your lower transmission mount/torque rod, it might be a little worn out and transferring vibration into the cabin.