G56 and US gear overdrive

[Byrdseye]

I'm hoping to install a US Gear Overdrive between my G56 and NV271... ... . I know that they are out of production and that they never made one for this particular application, but I think I'll try to find a used one and make whatever adapters is required. Does anyone know the spline count and diameter for the G56 output is? What about the 271 input. This may be a fools errand but it should at least be an interesting project.

 

[Regcabguy]

Hopefully,that'll work out for you. It'll be cost effective. My friend had a Gear Vendor installed on his G-56 and doesn't think he'd do it again because of the $4,000 installed price.

 

[ENafziger]

You may consider running a divorced setup... unless there's a need for you to split gears in 4wd.

I looked around and found a Mitchell gear splitter, that is a manually activated unit similar to the U. S. Gear. It's a 2-speed, that offers direct and 18. 2% overdrive.

If I was to do it over again, I'd probably look into other options, especially if you have some fab skills.

The Brownie auxilliary transmissions are readily available, and very cheap at around $300 - 400 in good condition. There are many models available, but I'd be tempted to try a Brownie Spicer 6041 or similar. It's a 4-speed that offers around a 2:1 reduction for extra-low splitting. This is non-synchronized, and must stop to engage/disengage. The other three gears are synchronized and are a under/direct/over configuration.

I made the frame cross members and mounts, as well as the shift linkage. It was only around $80 for the driveshaft modifications and balancing to be done.

--Eric

 

[Byrdseye]

Divorced is a good idea... ... ... especially if it turns out to be to much work to go in between the transmission/transfer. I really only need the overdrive when in 2WD and running down the road. I don't want to go with the Gear Vendors unit because of the cost and its problems with an exhaust brake... ..... thanks, this opens up more possibilities.

 

[cksh8me]

You're running a 35 or 36 in tall tire and you need more on top????? Good for you.

 

[ENafziger]

You're running a 35 or 36 in tall tire and you need more on top????? Good for you.

Actually, I'm running 37s with 3. 73s and the G56 and I really appreciate the 18. 2% overdrive for running around empty...

--Eric