I just finished installing a Gear vendors splitter. I did the install myself exept for shortening the driveshaft. It is expensive and I know I will probably never achieve a payback but it sure does make the truck more drivable.
75MPH or 120 Kms is now 1700rpm in double overdrive instead of 2250rpm.
Jim O

 

Let us know how long the clutches last,especially with a Jake brake.

 

Does anyone know what RPM your turn at 70 mph in 6th OD with a gearvendor splitter on a G56 tranny with 3:73 rears?

Thanks in advance...........

 

Mine is a 6sp, 3.55 rear, its at 1500 rpms at 70mph, doesn't get to 2000rpm til 90mph!

 

With a 6-speed, the U.S. Gear unit is a much better match, especially if one is towing and using an e-brake.

Rusty

 

I would be interested in something like that for my auto, but mostly for the gear reduction in the low end, and no more OD... I don't need anymore...

 

You can get the GearVendors unit (more suited for the automatic) or the U.S. Gear unit as an underdrive as well as an overdrive.

Rusty

 

I thought of the clutches and I wired a relay so that when the GV is in overdrive the ex brake will not work. The relay open circuits the yellow wire on the jake brake preventing the brake from working when the overdrive solinoid is energized. The GV unit is a .78 to 1 ratio. I chose it over the US gear as I did not want to move the transfer case and lengthen the front drive shaft. also I drove trucks with both units (US gear & Gear vendors) and I liked the way the Gear vendors worked best. I understand that you can get different ratios with the US gear unit but you can't with the gear vendors. The gear vendors is not really an underdrive ( you can't get a gear below 1st.) they call it an overdrive underdrive because you can split gears with it.
And finally if I could have ordered my truck with a 3.55 ratio, I would have and towed in fifth. and would have never had to buy the gear vendors. As it is I will probably pull in fifth over and use double over for bobtailing down the freeway.

 

Way to go Jim, congrats. I am sure you will enjoy the added fun of driving and the immediate savings on fuel. I want an auxilary trans just haven't had the money.