I'm hopping so, with the 37" tires the 4:56 gears should give me a good advantage over the 3:73's, With the cam and stall the gears were all that was left to get this thing moving

Neal

 

Thought I would offer an update with my impressions of the 4:56 gears,

First, I think it’s important to list all the modifications I’ve done to my 08 H2 so everyone has an understanding where I started from.

To start with I purchased my truck used with 146.00 miles on the clock and it had been neglected to some degree. I cleaned it up fixed the issues like cam position actuator, all gaskets that were leaking and drove it like that. The tires were worn and needed replacing so I lifted the truck with a lvl kit (raised the rear 1.5” and the front around 2 to 2.5” then installed true 37 X 12.50 tires.

I pulled the motor and added a GPI VVT-2 cam along with LS7 lifters, coated the piston heads with a CeraKote heat treatment along with coating the piston skirts with a dry film lubricant. The block was honed and I installed new hand fit rings along with polishing the wrist pins. All tolerances were checked and validated to be within GM spec’s. For the trans I used the stock build but installed a Circle D 2600 stall. For the exhaust I went with a full SS Speed Engineering setup, they didn’t have one for the H2 so I ordered a system for a 2500 series truck and built it to fit my truck. I used their long tube headers and full 3” system along with their straight through mufflers (I did install some custom fit auger mufflers to bring the sound level to where I wanted it), I also install an X-pipe and still have CAT’S on the truck.

The truck in stock form struggled to use 6th gear for anything but flat lvl hwy driving and any slight throttle input would cause the trans to downshift and adding the 37” tires made this worse. With the engine upgrade it was a lot better but still downshifted a lot, now the truck has the manual shifting option so its really nothing to set the trans to only use 1st thru 5th gear.

After the mods the truck ran really well and was a good bit more fun to drive. I have HP Tuners and have done all the tuning except for the initial tune; GPI did the tune initially to get it running then I took over. I’ve been driving the truck for a couple years I guess like this but had purchased the gears right after getting the engine back in (had been working on one of my other trucks so gear install got delayed).

So to the gear install, The truck should have come with the 4;10 gears as the earlier models had, my thoughts. The truck is a lot more fun to drive now, quicker from a stop and a lot quicker to 6200 rpm. It now uses 6th gear with ease, can accelerate while in 6th without downshifting and can cross all but the steepest hills (bridges, it’s flat here) while maintaining 6th gear.

All in all I like the truck as it is now, my plans were to install a blower but for now I think I’ll drive it as it is for a while then re-evaluate the blower in the future.

Neal,