A little back story, my engine died last summer. This spring I bought a used engine and started the swap. Then a bunch of things happened and everything got put on hold. The front of the car was up on jack stands since May until beginning of July. At some point I noticed that I lost a quart or two of tranny fluid. So I finally get everything together and take it for a test drive and it was shifting hard so I dropped the pan, changed the filter and put it all back together. Now when I shift into reverse there's a rough almost vibration, (sitting still or moving), it doesn't do this in drive.
It now shifts fine while I'm driving and takes off fine but it does shift kinda hard going from P-R, R-N, N-D. Any ideas?