I have a 1980, K2500, 350, 4 spd auto. The truck was totally restored a few years ago - new crate motor, rebuilt trans and transfer case, new torque convertor,etc., plus new sheet metal, paint etc. The truck has been driven less than 5K miles per year since rebuild. When I put it into storage, in Nov 09, everything worked fine. When I pulled it out, yesterday, it will not shift into high gear. I drove it approx 15 miles, and shifted it, manually, up & down through the gears -- No results. -- Any ideas ?? -- --

 

Try changing the fluid and filter first. Also unplug ALL connectors and check them and plug them back in.

 

-- Thanks - Will try. It will be a few days, the truck is at my cabin.