i have a doozy for anyone that wants to take a stab at this. i have a 92 chevy 3/4 ton with the 6.5 litre turbo diesel in it and it has had transmission work done to it but here recently when ever you go down the highway in 2wd the tranny feels like it is slipping but as soon as you put it into 4wd high it doesnt slip at all NEED HELP im going crazy about this truck