What transmission to run on 6.0

[Busters]

I have a question based on my 1998 Chevy C1500 so it has the 4L60e can I run a 6.0L out of the 1999-2006 engine with my current transmission, or do I need the 4L80e?

 

[NickTransmissions]

I have a question based on my 1998 Chevy C1500 so it has the 4L60e can I run a 6.0L out of the 1999-2006 engine with my current transmission, or do I need the 4L80e?

You would need to swap the existing 4L60E with a Gen3-compatible 4L60e anyways so Id just grab a good 4L80e, perform a segment swap for your pcm so it can control the 80 and run an aftermarket conversion harness or convert yours. You will also need to move your trans X-member back and cut/rebalance the driveline if it's a one piece design.

 

[Moofus02]

I had a 4l65 and 6l in my caddy. It was a beast when the converter flashes to 3500rpm but ducked as a Dailey driver. The tranny held up ok but I smoked it when I picked up a misfire at 90mph with the radio cranked and didn't catch the converter unlock until I was at 340 trans temp and lost front seal. That finished it. If I was swapping I would put in the 4l80 if for nothing else but the tighter 1/2 shift rpm spread. At 6k rpm second gear would drop that 6l below where it wanted to run. Strength is another factor. Can't beat the 4l80/85 for strength. It held up fine behind my 8.1 making over 500ftlb in a k2500 suburban