Transmission Overdrive Slip

Hey, got a 95 Lumnia 3.4 89k mi. Last couple of months noticed after driving a while in 5th or overdrive it starts shifting back and forth to a lower gear. Now it does it regularly even in town. Had trans fluid changed about month ago, didn't help. Anti-lock brake light comes on occasionally. Any thoughts or self-help remidies appreicated

Sounds like the famed TCC solenoid locking up and unlocking. Does it do it when you go up a hill or on level ground too? Kinda like a surge or an actual downshift-upshift?

Hey, got a 95 Lumnia 3.4 89k mi. Last couple of months noticed after driving a while in 5th or overdrive it starts shifting back and forth to a lower gear. Now it does it regularly even in town. Had trans fluid changed about month ago, didn't help. Anti-lock brake light comes on occasionally. Any thoughts or self-help remidies appreicated

Thanks for the reply. yes to up hill and level ground, and more like a surge. Feels like its shifting. Example, 60mph 2300rpm, then all the sudden 3000rpm. If on interstate it will stay at3000 untill I stop for about 10 min. Also if I'm going down a hill it seems like it is shifting back and forth.