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Turn your 2 speed Atlas into a 4 speed...

   So, you've got yourself an Atlas, but now your needing more gearing. No problem. 

We have a Strong Box Shorty designed specifically for the Atlas 2 speed. What can the Strong Box Shorty do for the Atlas? Below is a gearing example:

     4:1 Atlas II + 2.72:1 Strong Box Shorty = 1:1, 2.72:1, 4:1, and 10.88:1.

            4 different speeds with the lowest being an incredible 10.88:1. All packed into a transfer case assembly that can be as short as 16". 

    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. 

​Atlas II Strong Box Shorty DIY kit $699.00
​Pre-Assembly / Good, Used Gears $300.00