The Idea:
Since the dawn of rockcrawling, Jeepers have been tripping over themselves to get the latest and greatest drivetrain components under their Jeeps.
It seems that either you drop $6,000 and put in a high-end aftermarket axle, or you spend a little at a time to build up what you've already got in your Jeep. The problem with the high-end axle, assuming you can come up with the cash in one shot, is that you then have to throw away whatever you've invested in your current axles.
Too many people are overbuilding their Jeeps and getting rid of the stock axles when they don't really have to. What we've done is take all of the stoutest components available for the stock Jeep Dana 30 front axle, added some elbow grease, and took it wheeling.
The Dana 30 gets a bad reputation from guys pushing it way too hard. For what most Jeepers do, the 30 is just fine.
The Build Summary:
First we started with a non-vacuum disconnect, high-pinion front axle from an '89 Cherokee. With the high-pinion, it'll be stronger in the front of our YJ, and by ditching the cast vacuum disconnect junk, we don't have to worry about exploding cast steel pieces.
We then got a Dana/Spicer 4.56 ring-and-pinion set and Yukon Gear master install kit from Randy's Ring and Pinion, added a prototype 30-spline OX locker, 1.31-inch diameter 30-spline Superior inner axleshafts, and 27-spline chromoly Superior stub shafts held together with OX's axleshaft U-joints and Superior's outer axle seals (to keep mud and sand out of the tubes). This is all going into a SOA YJ, so we picked up M.O.R.E.'s steering correction kit for YJs and their YJ spring perches.
We then reused the YJ outer knuckles and unit bearings. We took the XJ housing, lopped off all the goofy coil spring stuff, added a truss, and beat on it with a 4.7L stroker and 38-inch Super Swamper TSLs.
Oh, and it survived just fine.
Our Final Thought:
While this might not be the way to go for everybody, it sure appeals to us because of the ability to do it a little at a time. Yeah, it's a lot of cash tied up in a Dana 30, but if you were to do it piece by piece and build the axle as your need grew, it'd work just fine. With the high-pinion centersection and lack of the vacuum disconnect casting on the long-side axletube, the housing is fairly strong. With that truss, it's almost unbreakable.
We think that the 38s are a little big for this axle and wouldn't suggest it except to make a point. This Jeep will end up running 35s with that stroker and a manual transmission. We think that the Dana 30 will hold up just fine. Stay tuned. In six months or so we'll let you know what broke and what didn't.
We decided that the normal 1-inch diameter, .219-wall tube that comes with the M.O.R.E. steering correction kit wasn't extreme enough. So we uprgraded to 1 1/2-inch diameter, .250-wall tube for the ultimate in bashability. | 
Once we lopped off the XJ brackets we didn't need and pulled the axle apart, we took it to M.I.T. Drivetrain Specialists in El Cajon, California. Andy Thomas took care of the install for us, but first he had to remove the old pinion races that we'd missed in disassembly. | 
The high-steer arm is the key to the Mountain Off Road kit. The only tool we didn't have on hand was a 3/8-24 tap for the trio of bolts seen here. |
Since this was to be the ultimate Dana 30 and the YJ it was going in sees air somewhat regularly, we trussed it. Using 1 1/2-inch diameter, 0.125-wall DOM tube and a 3/16-inch plate, we figure the outer knuckles will break before the housing bends. | 
Not more than five hours later, we had the OX in the housing with the Dana Spicer gears and were ready to move on to the next step. The Dana Spicer gears come with setup shims and pinion bearings. The 30-spline OX locker comes with inner axle seals, shims and carrier bearings. We only ended up using the slinger and the marking compound from the Yukon Gear install kit. | 
From the prototype OX to the Superior shafts, from the Dana Spicer gears to the M.O.R.E. steering kit, the only problem we had in the install or on the trail was those huge tie rods we just had to have. While Mountain Off Road includes spacers in their kit, we chose not to use them, and due to the design of the high-steer arm we had to put the tie rod on the knuckle. We ended up with just under 1/4 inch of clearance from the tie rod to the spring. |