Call/Text 1(270) 287-8663      Email:

   The NP205 Strong Box Shorty is compatible with any married NP205; round 6 bolt, or figure 8 bolt pattern. When using a figure 8 NP205, 3 of the 8 bolts will not be used. We recommend adding a mount to support the additional weight of the 4 speed assembly, no matter which NP205 you are using. 

   Any NP205 with a male input shaft (besides a Dodge 29 spline), will have a small bore (80mm / 3.15") input bearing pocket. 

  Any NP205 with a female input shaft will have a large bore (90mm / 3.544") input bearing pocket. The Dodge 29 spline male shaft also used the large bore. 

   When ordering, let us know which version NP205 you have. If your NP205 is still installed in a vehicle, tell us what transmission it is bolted to, and we can likely determine which version it is, if you cannot.

   The NP205 has proved to be arguably the strongest transfer case ever produced for road vehicles. No wonder it is so popular with those who like to drive where there is no road. 


  Our standard Strong Box Underdrive works well with the NP205, but sometimes the added length makes driveline angles a nightmare in short wheel base vehicles. 

   That's when you need the NP205 Strong Box Shorty. Same incredible gear strength as the standard Strong Box, but 2.4" shorter. By combining the dimensions of the Strong Box output shaft with those of the NP205 input shaft, you have a one-piece intermediate shaft. The male / female splined coupling section of the two shafts is deleted. 

    Our line of 2.72 Strong Boxes are designed to use gears from the following transfer cases:

NP241, NP243, NP246, NP231, NP233, NP236, and a few others that are very similar.  

   To use NV271 or NV273 gears in the 2.72:1 Strong Box Underdrive, you simply need to order your Strong Box specifically for NV271 or NV273 gears. We will make sure your Strong Box gear housing has the proper dimensions for NV271 / NV273. If you have already received a housing machined for NP241 or similar gears, we can modify it to accept NV271 / NV273 gears easily, and at no additional charge. You only pay shipping cost. NOTE: A NV271 / NV273 housing cannot be modified for NP241 or similar gears. 

Other cases that can be used, but may require slight modifications include:

NP261, NP263, NP241 DLD, and a few others that are very similar.  Click Here to learn more about some of the required modifications to use these gear sets. 

    This allows the 2.72:1 Strong Box to be ordered with any of the following input shaft spline counts, making it compatible with many domestic transmissions:

  • 21 spline Jeep
  • 23 spline Jeep / Dodge
  • 24 spline Ford
  • 27 spline Chevy
  • 29 spline Dodge
  • 31 spline Ford
  • 32 spline Chevy
  • 34 spline Ford

Don't see the spline count that your transmission output requires?...

Keep looking on our site, we have other options available, and more to come. Feel free to Contact Us with your custom need. 

NP205 Strong Box Shorty DIY kit $999.00
​Pre-Assembly / Good, Used Gears $300.00

NP205 Strong Box Shorty