I have a 97 Sunfire, 2.2 L motor and auto tranny, not sure if it has some type of overdrive tranny, gauge cluster shows PRND12. What makes me think it has O/D is--when I drive at highway speeds on flat ground the tranny will upshift and I count the gears, the RPM will go to say 2800 rpm then it will seem to shift ( hard to feel it) but looking at the tach the rpm's drop to 2500, this is great but lately it started shifting back and forth --2800 rpm then 2500 then 2800 then 2500---I checked all kinds of things even adjust the TV cable like the manual said (it shifted way more positive) but the 2800-2500-2800 rpm didn't change. I noticed if I lifted on the brake pedal it would stay in the lower rpm until I let the pedal go, the it would shift and rpm's would go back up--I could make it do this anytime at highway speed---this lead me to an adjustment at the brake pedal, I adjusted the switches (yes 2, assume 1 for brake lite and other for tranny lockup), plungers all the way in when pedal is up, now it doesn't seem to shift into O/D. Am I dreaming on this shifting, does anyone know what tranny is in this car. thanks
