Ok so i just had the trans rebuilt by a fairly highly rated trans shop, and ive had nothing but problems out of it! When i first got it back it was falling out of gear at idle, and would only engage when revved. Then it started over heating and the tuner would show it commanding gears at the wrong time, i took it back to him and he pulled the valve body so check some things and he put a 2nd set of new solenoids in it. I got the truck and added a 2nd stock cooler and 2 fans in his parking lot along with new sensors. Still overheating, and now it was starting in 3rd until 5mph then go to 1st and shift like a dream. I got it out on the highway that day and it cooled down and worked like a dream for a day. Then it started trying to be in 1st and reverse at the same time. New harness in and out, fluids and filters, no luck. Finally i was on a test drive for the harness.and it locked up on me coming up to a light. Pulled it, low/rev, forward and od clutches all welded. When i pulled the pan the safety switch was melted bad, but the temps never got above 250. What could have caused all of this? The park neutral safety switch? He messed up in there somewhere? What the heck? I put 4grand in this truck, 2500 for the trans plus all the other things between install and diag of the issue. If anyone has an idea please step in.