Economical Off-Road Trailer Build - Part IV

The Ultra-Tow spindle was fit in the end of a 2-inch-by-0.120-inch-wall tube.

For tires and wheels I planned to install a set of 31x10.50R15 BFGoodrich Mud Terrains mounted to 15x8 Rugged Ridge steel wheels with 3.75 inches backspacing.

With the tires mounted and balanced we measured the distance from the wheel face to the edge of the tire to help determine the axle width.

We then applied that figure to the spindle and tube. I wanted to leave about a 2-inch gap between the trailer side and the tire to minimize rubbing when the trailer twists up on the trail.

Once I figured where the tire needed to be I measured from the spring centers out to the spindle ends. I doubled this figure and added it to the distance between the spring centers to figure the overall axle length.

After the tube was cut to length my neighbor, Steve the blacksmith, cross-drilled the tube ends so plug welds could be applied.

Steve the blacksmith welded the spindles to the tube ends much more quickly and efficiently than I could have. I was jealous of his new Rockwell Jaw Horse.

With the spindles welded to the tube I set it in place over the leaf springs using the Omix-Ada spring perches and some used U-bolts and U-bolt plates that I found in the garage. I’ll need to order custom U-bolts for the 2-inch-diameter axle tube. I’d initially thought I’d run the springs over the axle but it simply provided too tall of a ride height. Set up spring under the ride height was just about perfect.

The Ultra-Tow hubs from Northern Tool & Equipment came pre-greased and ready for installation. They offer a 5 on 4 1/2-inch wheel bolt pattern, which is the same used on Jeep YJ and TJ Wranglers and also the Jeep Cherokee XJ, among others.

With the tires and wheels in place and the trailer on the ground I could see that the shackle hangers needed to be moved back about an inch.

As they are they kick back too much with the trailer unloaded. Once loaded the shackles would likely kick back all the way to the frame.

Now it’s starting to come together. The 31x10.50R15 BFGoodrich Mud Terrains and Omix-Ada CJ leaf springs offer ample lift and ground clearance for towing behind my Grand Cherokee WJ and Cherokee XJ. If I ever want to go taller I can easily run spring over axle and fit a 33- to 35-inch tire. The ARB Simpson III rooftop tent was set on the deck sans mattress to see get an idea of the trailer’s overall height.

I needed to devise a method to hang the Shipshape Jeep-style fenders from Northern Tool & Equipment. After scratching my head for too long I came up with a simple plan of a center support off the center upright.

I then used a Sawzall to notch the center of the fender so it would sit flush to the trailer side. I pre-drilled the mounting holes in the support and then used a scribe to mark holes to be drilled in the fender. Once the fenders were bolted in place I marked and drilled holes at the bottom corners of the fenders and bolted then to the bottom of the trailer frame.

Here’s how the fenders turned out. I didn’t make the notch large enough on the first fender I cut so I ended up with two extra drilled holes that I can live with. There is still ample space to stuff the tire in the fender in an upward direction but not a lot to the front or rear. I may remove the fenders and try to bend them out a bit to create more unobstructed space for the tire.