Quote Originally Posted by arveetek View Post
Factory 6.5L in 1994 would be a one-piece seal. You would HAVE to remove the transmission to replace it, so it's definitely worth doing with the transmission out of the way anyway.

Casey
This would also be a good time to deal with leaky engine oil cooler lines, especially if the vehicle is on a lift.

Secondarily... the factory 4L80-E came from GM with a great pan gasket. It was made from aluminum with an o-ring seal. This gasket does not need to be replaced - it's re-usable. Rebuilders usually toss it... and install something less good.