Wow, a S6-650 behind a 6.2L must be like driving a race car engine backed by a dump truck transmission
Glad you like yours….you could have the ZF S6-650 in my 2001 2500HD. I hate the damn thing. Worst shifting manual trans I’ve ever owned with an even worse shift pattern. I’ve own that truck since new and 13 years later it has finally started to loosen up where it isn’t quite as notchy as it was up to this point (It just turned 59,000 miles last week) but I still hate it. The clutch pedal geometry on the GMT900 trucks is also quite funky. There is no slip to it, it works like an on/off switch where it is almost impossible to launch the truck smoothly. Between the clutch operation and the awkward shifting ZF 6 speed is why it has only racked up 59K in 13 years. I don’t like to drive it much.
I still prefer a NV4500 over the ZF any day, but there is no doubt about it the ZF is a much stronger transmission by a long shot.