I have a 2003 2500HD with a 6.0. I downloaded the Predator program (by the way I am totally happy with felt like a different truck.) I did the stock program then changed the shift time to -25% and shift pressure to + 25% but my question is floored in drive the trans shifts at 5,200. I was thinking about raising 1st and 2nd shifts to 5,800. I don't know if that will be to high or not but I shift my 6spd 2002 SS at 6,000 RPM and dyno #'s showed that it pulled right up till 6,000 RPM. Do you think 5,800 for my truck would be to high as it will see that quite often? Any help would be appreciated!

 

Yeah, that'll help you quite a bit. Mine are I think 5850 for 1-2, and 5700 for 2-3. The key is to make the tach land at around 3500 or so after the shift so you don't drop out of the powerband.

 

watch out for the tranny though...the 4L80-E is rated by GM to shift at 5200 RPM's...it's probably underrated but still......