Shift Points

[Redfishtony]

Just replaced the head gasket on my 1997. After getting it back together it runs great however now the automatic trans is not shifting correctly. The shift points are way to high. It will shift fine but shifts from 1-2 @ 3k, 2-3 @ 4.5k, 3-4@5500 then OD @ 70 mph. Any ideas? Is there something I got out of adjustment during the rebuild? Help please. Thanks

 

[Joisey]

If your transmission uses a vacuum modulator, the line may be disconnected or leaking. Low vacuum at the modulator tells the transmission that the engine is under heavy load, such as climbing a steep hill or holding the pedal to the metal. Both will cause the transmission to upshift much later than normal.

If you don't have a vacuum modulator, you may have a wire broken or disconnected that controls upshift, or perhaps a ground wire that wasn't replaced.