1992 chevy 1500 shortbed step side 2wd

Kudos on changing your transmission fluid. This is a common over looked procedure. In almost every case the transmission fluid level is low when you have to rev the engine high to get the car to go. That being said, I would double and triple check the fluid level on the transmission. The Transmission fluid level should be checked with the engine running and parked on level surface. It can be difficult to read sometimes on the dipstick when filling as the fluid doesn’t want to drain out of the tube very quickly.