I have a 1994 chevy ck 1500 siverado 5.7 that hangs in 2nd gear and revs up at about 30 to35 miles per hour and will not shift in to 3rd or or 0verdrive . This only once in awhile. I have had the truck 6 years and this has happen 3 mabe 4 times. Dennisy
When the rpms of the engine are up there, let off the gas pedal a little bit to allow it to shift. But this age truck I'm sure there are a lot of miles on it, these transmissions usually only last 140,000 to 200,000 miles before a rebuild it time. But you could stop at a trany shop and have them check to see if any shift solenoids are getting bad that they could change.
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