Universal Strong Box Underdrive For NP231/241 And Similar, and NV271/273 And Similar, Standard Length, DIY Kit
Our 2.72:1 standard length Strong Box Underdrive is the most versatile and universal of all of our torque multiplying gear boxes.
Measuring only 7.9" long X 7.9" diameter, and weighing 36-39 pounds when loaded with gears.
4340 alloy steel is mainly used for manufacturing landing gear for heavy aircraft. Our 4340 thru hardened shafts come with a Limited Lifetime Warranty* against breakage.
We use a rear bearing to support the output shaft, and keep all components concentric.
Our standard length Strong Box Underdrive can mount to nearly any domestic transmission and transfer case. Ford, GM, Dodge, and Jeep transmissions and transfer cases with the round 6 bolt pattern, and a female input shaft, can bolt to the Strong Box.
There are 3 sections to the standard Strong Box housing. First, the gear housing. Next, the shifter housing. Finally, the clocking adapter. Each section has multiple universal bolt patterns which allow nearly infinite clocking positions for your Strong Box shifter mechanism, and for your transfer case.
NOTE: The Universal Strong Box for 241/271 style gears is designed to work in front of a transfer case with an input shaft that sticks out 1.7" or less. If your input shaft sticks out longer than this, you will need to trim it.
Some models of the NP205 transfer case came with a long (about 4" of stick out) female 32 spline input shaft. This is one exception. To use this NP205 with the Strong Box, you would need an additional 2.2" long spacer, or swap in an NP205 short female input shaft.
DIY kit typically ships within 21 days from order.
Want a Strong Box with gears already installed and to bolt in?