1997 2WD Tranny problem

My '97 silverado has 90,000 miles on it. Here's the scenario: If I do a long run (>20 minutes) at a steady 70 - 80 mph speed, then stop and start out again - when the tranny shifts from 1st to 2nd, it slams into 2nd gear so hard it'll chirp the tires (not to mention snap your neck). It does the same shifting into higher gears but is felt less with each higher gear. From there on, it will continue to shift in this manner until the vehicle is shut off and restarted. Took me a while to realize it, but turning the key off deenergizes something in the tranny brain and it seems reset something and shifting goes back to normal. The tranny does not slip that I have ever noticed. I have only gotten it to do this about 5 times in the past year or so. It's always been after a long run at steady, high speeds. Any thoughts on problem?

Thanks,

Dale

I had that same exact problem with my Silverado. I bought it with 86,000 miles already on it. I have changed the fluid and filter screen, and it helped a little but not much. I have described the problem to several mechanics and heard a few different answers. One told me to go to a transmisson place with a good reputation and have it thuroughly flushed that the transmission has probably been neglected and the tranmission fluid is not flowing through to the shift valves properly which causes the hard shifts. Also with that being said. If you cant remember the last time the transmission has been serviced or you bought it with some miles already on it and dont know the history of it. It would be best to have it serviced also. I would also have an experienced tech look at it. I let mine go because one of the mechanics said that I could run like that for ever if it didnt bother me. I meant to have it eventually fixed but wasn't worried because of what that mechanic said and my transmission eventually went out. Now I have to have it completely rebuilt. So dont delay too much. I hope this helps you some.