After we found what Currie Enterprises charged for cutting down an axle and axleshaft, we were sold. This is our short-side shaft in the CNC mill getting resplined.
Our '94 YJ has made a few cameos before, but because it's not a month-by-month kind of project vehicle, let us introduce it again.
This is the YJ with more than 350,000 miles on the clock, just as much rust as good metal, a four-cylinder engine, five-speed, about 1 1/2 inches of lift, and a soft top. It is not a trail monster but rather a daily driver that gets driven to the trail and then driven home.
We had just swapped a set of 33s onto the Jeep, and the stock 4.10 gears just weren't cutting it. We knew we wanted 5.14 gears and an axle we could wheel with all weekend and not worry about. We wanted to do this without breaking the bank or affecting the street manners of the Jeep. Basically, we were after fullsize-strength axles without the fullsize width or price.
This first part of the Wrecking Yard YJ will cover the rear axle, with the front axle being covered in the next issue. Follow along as we shoehorn some big axles under a little Jeep.
We settled on a later-model Ford 9-inch axle from a pickup. That got us 31-spline axleshafts, big axle bearings, a stronger housing than earlier models, and the most aftermarket support of any differential. | 
Another possible problem is some of the older axles weren't heat-treated enough to safely cut new splines into. The first picture is a Currie axle with plenty of depth to the heat-treating, and the second is our stock axleshaft with just enough depth.(continue) |
Unfortunately, the only way to figure out if the axle was heat-treated right is to cut it to length and look at the depth. Currie Enterprises does this as part of the service. | 
We didn't think anything of the surface rust on the axle, but after getting it home from the junkyard and getting the brakes off of it, it was clear that this thing hadn't moved in quite a while. The drums were cracked, the springs were too rusted to use, and the adjusters seized. Save yourself some money and check before leaving the junkyard. |
The 31-spline axleshafts are tapered toward the ends, which means about 4 1/2 inches of axle needs to be cut off before it can be resplined. | 
After the housing is straightened, the end is tacked back on and then welded in this jig. After it is fully welded, the axle is again checked with an alignment bar and straightened if necessary. Not bad for $100. |
Final Costs
While the axle didn't turn out as cheap as we were aiming for, it is still a decent price for an axle with a traction-aiding device that will take us to the trail and back without any fear of us destroying it. And don't forget the final tally includes everything needed to install it in the Jeep, ready to drive down the road.