Early Jeep Axle Swap
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Attn: Christian Lee
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Early Jeep Axle Swap
Q:First, I'd like to say thank you for all the stories and pictures of adventures out and about in the desert (like the October 2011 issue). I've been deployed for a little over eight months now, and every time I read an article and see the pics of a run, it brings back all the great memories of 'wheeling back home with family.
Second, I know you guys want us to ask questions and such, so here is mine. I own a '56 CJ3B and have many upgrades I'd like to make to it. It's a family rig since '78, and I just want to upgrade it a bit to withstand the treks and stay with the times. I've installed a Chevy 350 and have a Muncie 4 speed (it's what dad had in it, so I kept it) and I want to put some nice axles/housings underneath it that will handle the power.
The issue I have is that the Jeep is back home in Arizona and I'm here in Iraq, so measuring to order close to the right fit is not an option. I want to do the easy thing and order both axle assemblies done and ready to bolt in. However, all the preassembled axles I've found are for '76-and-newer CJs and all the latest Jeeps. I have no problem with making minor modifications to the housings to make them fit (cut/weld tabs). I don't know the size and/or style I should buy. Will a '76 axle housing bolt up to mine? Does anyone make an axle assembly that will?
Thanks again for the good reads every month. I look forward to getting back out and Jeeping with friends and family. Maybe I'll send in some pics of the dogface.
Sgt. 1st Class Beau Woodcox
U.S. Army, 7th Engineer Dive Team
A:Beau, thanks for your letter (and thanks for serving our country!). This sounds like a great project. You have some options when it comes to upgrading your factory axles in your CJ-3B, but some will require more modifications than others. The reason you can only find pre-made axle assemblies for 1976-and-newer Jeeps is that most earlier model years used narrow-track axles (53-inch width) that are often upgraded to later model wide-track axles (56-inch width).
Your '56 uses a front axle that is even narrower than the narrow-track at 51 inches wide and also uses closed steering knuckles as opposed to the open knuckles used in later models. This means if you use the later narrow-track or wide-track axles your tires will stick out from the fenders a few more inches. Some will go this route and install wider fender flares to cover the tires. This is a good route if you are also installing taller suspension and taller and wider tires but will look a bit silly if not. With this in mind you can almost bolt-in a narrow-track axle and can cut down the wide-track axle to make it fit your needs. A variety of good narrow-track and wide-track donor axle candidates are available but some are in short supply.
Be aware of axle offset when selecting a swap candidate: your Dana 25 front axle is offset to the passenger-side and your Dana 44 rear diff is centered. In using a wide-track axle it is often necessary to “out board” your leaf springs from the frame using new spring mounts since the spring pads on the axle tubes are wider apart than the spring mounts on the frame.
Also, in addition to being wider, later model axles were also paired with Saginaw steering and used open steering knuckles so swapping in a new axle is also time to replace the factory bell crank steering arrangement. Advance Adapters [(800) 655-0787, www.advanceadapters.com] offers a good kit for completing this steering conversion. The easier yet higher-priced option in axle swapping is to call a competent axle builder and have them build your axle to your specs ready to bolt-in to your Jeep. Hope this helps. 'Wheel on.