Hello, I have a 1998 Lumina 3.1. The RPM's seem way too high while driving. Example: at a cruising speed of 55 MPH the RPM's run at 2500, at a cruising speed of 75 MPH the RPM's run at 3500. The car drives fine, I just feel the RPM's should drop once I get to a higher gear. Any guru's out there have any ideas? Thanks.

Stop on a entrance ramp and then count the upshifts. You should get three (1-2, 2-3, 3-4)

Sounds like you're not hitting OD...could be a solenoid stuck or something more serious.

Stop on a entrance ramp and then count the upshifts. You should get three (1-2, 2-3, 3-4)

Sounds like you're not hitting OD...could be a solenoid stuck or something more serious.
Looks like there is no 4th gear. I guess that means new transmission.

Maybe not, should be scanned with a trans function scanner for solenoid functions and slippage errors. The 4th gear clutch hub can cause this also.