what gears

[knez]

Hello everyone.Hey guys new to the forum.Im lifting my truck 6in and putting 35in tires on a 04 2500hd 8.1L 4x4 with 3.73 rear gears.What ratio gears should i run 4.10 or 4.56 and as for the computer from what I ve seen no after market tuner for gear changes on the 8.1l with allisons only tire adjustment and engine performance.Any help would be greatly appreciated.

[Shotgun]

Well my vote is for 4.56"s. I am running them with 33" tires and I think they would also work pretty well with 35"'s.I am running around 2400 RPM @ 70MPH. 4.10's wouldn't be worth changing to. in my opinion.

[knez]

I see you have hypertech will it adjust for gear change?On there site it said it wouldn't on my drivetrain.Is there one that will?Thanks for the reply.

[Frank S]

I believe even with the Allison transmission you can adjust for different gears.I think you are pretty much stuck with your stock shift points and firmness but I'm pretty sure you can change for gears.

[Shotgun]

I see you have hypertech will it adjust for gear change?On there site it said it wouldn't on my drivetrain.Is there one that will?Thanks for the reply.

Yes I used the hypertec to adjust for gear and tire size. I'm not sure if any of the programmers can adjust your speedo with the allison.