I am way more familiar with standard trans's than automatics. I need some help diagnosing this problem.
I recently had a new rear trans seal because it was leaking and then the trans seemed decent for awhile. Then it started slipping and the fluid level was low so I topped it off and then the fluid level was low again and I topped it off. Now it is slipping again, especially in reverse, but it has not lost any more fluid. The fluid does appear to be slighlty "browned." I had the fluid changed about a year ago before the rear seal started leaking. I do smell hot trans fluid after driving it sometimes, but I am parking it in the snow and I have never seen trans fluid on the ground, but I guess if it is brown it might just blend in with all the other brown slush. I was driving with no O.D. for awhile due to a bad relay that I have now fixed. The other thing I have just noticed is that the speedometer needle bounces once in awhile when stopped which it never used to do.
I don't know if I am looking at something plugged or if I need a new used trans. I have swapped many standard transmissions and have replaced clutchs and pressure plates etc. but I have never swapped an auto trans or a torque converter.
I would appreciate any and all help. Car has about 280,000 miles on it and it is our only daily driver...