I'm not sure if it's slipping or just plain not shifting properly. Started about a month ago at about 45-55mph. It would jump back and forth when trying to upshift, if I tried to gain speed it evenually shifts up ok and runs fine. Gotten more pronounced the past week or so. From about 35-50 if I'm on a slight grade then it does it. If not it shifts fine and it's fine as slower speeds even climbing a steep street. I'm really hoping this is not serious. I put 1/2 qt of fluid in it because it was low but did not help. Could it be a faulty speed sensor? Anyone who checks this out and responds I really appreciate it. I forgot to add, it appears if I shift to D3 it shifts ok if that helps.
Transmission shifting oddly on 1997 Oldsmobile Regency
by PensFan in Crescent, PA on January 03, 2010
ANSWER by dandd on January 03, 2010
Possibly you also have a Check Engine Light or Service Engine Soon Light on yes? I say this because it sounds like the Torque Converter Clutch of your transmission is wearing out, which is some what common on GM. check these links http://repairpal.com/check-engine-light http://repairpal.com/OBD-Code-P0740