4L60e will only move the truck for 30 seconds!!
 

bought a 1999.5 chevy 5.3L 3 door half ton 4x4 auto with 280,000 miles supposedly a rebuilt trannsmission with less than a thousand miles on it and a bad motor swapped the motor and drove for a few hundred miles then as i was getting on the turnpike it wouldnt go into over drive I stopped and took off again even slower this time pulled a u turn and almost made it back to a gas station then it went from topping off at 20 mph to nothing so I filled it up with tranny fluid then it worked for about 300ft and quit now if I turn it off for a couple minutes it will drive for about 30 seconds(still shows full of fluid) and then it feels just like someone pushed the clutch in but while I was waiting for a tow truck it leaked a puddle of tranny fluid from the top of it somewhere first leak i saw on it my only guess is it sprung a leak as I was getting on the turnpike and I toasted her

Does the dip stick smell off burnt fluid?

Once they start slipping, they burn in a hurry.

Allan

Ya it does I'm almost positive I burnt up the disc in it