I have a '92 F-150 w/E40D tranny. Tranny was rebuilt 40k miles ago and I have always had a problem with it killing my engine when I shift into reverse or 1st (low) but drive and 2nd are fine. This only happens when the tranny is warm during the summer when ambient temps are above 100 degrees. The rest of the year it is fine unless I'm doing heavy towing which I can let it idle for a couple of minutes and it works great. It seems like the torque converter locks up and stalls the engine, the trick I learned is as I shift into reverse to punch the gas momentarily to unlock it, this works most of the time unless I've been towing or doing much city driving when it's hot out which then I have to keep one foot on the brake and one on the gas and hope it doesn't stall and I don't pull out in front of someone too fast! Any ideas? The solenoid pack was replaced at 3k miles due to the converter clutch solenoid was sticking. I'm don't think it's a pump pressure problem, or the converter, could the valve body have an issue? It was rebuilt in the winter and by the time I noticed it the warrenty was out. I do have a tranny cooler rated at 30K lbs GVWR which works pretty good.