Chevrolet Repair: 93 Chevy blazer, chevy blazer, transmission overhaul

Question
Transmission will not shift into next gear when I reach about 40 MPH.  If I let up on gas and hit gas again the transmission doesn't engage untill I drop back down to about 20 MPH.   The fluid level was low by 3 quarts and refilled but still doing same thing.  Any advise.  I don't want to have a transmission overhaul.   Thanks,  Dan

Answer
Hello Dan,
I would drop the pan off the tranny, and see what the oil, filter, and sediment in the pan looks like.
If the oil is dark, and smells burnt, you could have a worn out clutch.
If the filter is real dirty, changing it and the oil may help, but if it ran slipping very long, it may be too late.

Van