Motobilt Tech Thursday "Full Width Axle Conversion"
- by Dan DuBose
Motobilt Tech Thursday “Full Width Axles”
Today’s Motobilt Tech Thursday will focus on full width axles for your Jeep CJ or Jeep YJ. One of the most popular modifications to do on a Jeep is to swap to bigger and stronger axles. This is true for most every Jeep out there! As you build your Jeep and ready it for off road, you soon realize the limitations of the stock axle assemblies as you transition into larger tires, bigger motors and harder wheeling.
Custom axle assemblies built specifically for your Jeep are fantastic but can be very expensive; this brings us to full width axles. A full width axle is an axle out of a larger truck such as a Chevy, Ford, or Dodge ½ ton, ¾ ton or 1 ton. These axles are much stronger and larger than your stock Jeep axles. Swapping these axles into the rear of your Jeep CJ or Jeep YJ is pretty straight forward. You simply need to relocate the leaf spring perches to the proper location on the axle to match your leaf springs.
Installation of the front axle is more complicated. You cannot simply move the spring perches as the perch on the differential end is a part of the assembly. If you moved that perch to match, you would have to cut down the long side axle tube. Otherwise the axle would stick out several inches further on one side than the other.
This is where the “Full Width Axle conversion kit” comes into play. The kit moves your spring perches outboard of the frame to match the width of the spring perches on your axle. You will want an axle with a center pin to center pin location of about 31 ¾”s to 32”s in width. If you use axles out of a newer truck, such as a Ford super duty, the width is much larger. These larger width axleswill not only not work with the kit, it will also create clearance issues with your tires. When you run larger tires like 37’s and up, your tires will often hit the leaf springs on these type of newer axles. This is why we recommend the older 78/79 type axles.
On a Jeep CJ the full width kit moves your spring perches approximately 2.5”s out on each side. On the jeep YJ it moves the perches out approximately 5/8” on each side as the YJ frame is wider than that of a CJ.
The design of the Jeep full width axle kit also utilizes a shackle reversal system. This allows you to move the shackle to the back of the spring instead of the front. This means that when you hit a bump in the road the spring will compress and swing backwards. This transition change may provide for a better ride on road.
The Motobilt full width kit is also designed with an integrated bumper and winch mount setup. This provides you with clevis mounts for your D ring shackles and a place to mount your winch. The design also allows for the front axle to be moved forward for increased wheel base and allows for a low center of gravity compared to other kits on the market.
If you are interested in the conversion then click the link https://www.motobilt.com/suspension/full-width-kits.html or call us at 334-219-2333