I disagree with most of the people that posted in this thread. Have a feeling they don't fully understand these transmissions based on their comments. Please don't take that as derogatory guys, allow me to explain.
99PontiacGTP: His trans isn't bad, he has a stripped 4th hub shaft. It's a $45 part plus fluid and about 3 hours to replace.
GTPEddie: Why is his trans weak already? A quick diff swap and he has an HD trans.
99pgtgp: I agree he'll likely kill it, based on his heavy right foot and added power.
Hitman: Jason..I'm surprised that the master of using a 4T60 with a top swap would call a bad 4th half dead. You proved that power on the usually considered weaker 60 was possible.
BMX do you realize what an HD conversion consists of? It's just a diff. if you didn't abuse the diff with burnouts etc..likely the non-hd would be fine.
Since you are talking top swap. I'd recommend pulling the whole drivetrain out the top. That makes all your engine work super easy on a stand. Then you can also toss a 4th hub shaft into the trans super easy. And if you felt like it..the HD diff.
