Here is my take on a swing away tire carrier for my TJ.
When I first got the Jeep in '05, I bought an OR Fab swing away tire carrier which mounted to the body only, and also held a jerry can and a tool box. That worked fine with my original 35's, and even held on through the 37" Krawlers. But after going to 40" Krawlers on Spider Locks, the weight was too much for the body mounts. I began to notice the the body was deforming and bending where the carrier mounted, and the right rear body mount was also bending due to the weight. Time for a change, or else stick to wheelin' the mall.
Given the weight of the Kralwers, it was very difficult to get the tire on and off of the carrier by myself, and I liked the idea of a swing down carrier (like the one built by Gen Wright) to help with that issue. But, I also need easy access to the tail gate as I have a large, pull out tool box that requires opening the tail gate to access. It would have been quite a workout swinging that 40" Kralwer up and down each time I needed to get into the tool box.
So, I came up with this idea for a swing down / swing out tire carrier.
My rear bumper is a sturdy unit from Body Amour. It's 3/16" 2x5 steel with solid mounts to the frame, so I felt this would work and save me the time of building a new one. First, I picked up a heavy duty 2500lb spindle assembly from A to Z Fab. This thing is beefy, and the main body of the spindle shaft is 2" in diameter. First step was to bore a 2" hole in the 2" bumper. I offset the hole toward the back of the bumper in such a way that in addition to welding the shaft to the bumper steel, I was also able to weld it directly to the 3/4" mounting plate behind the bumper stock which bolts to the Jeep frame. You can see just a bit of this plate in this picture.
Next, I began work on the swing arm. I came across a sweet latch mechanism from Poly Performance which is designed to work on 1 3/4" tube used for the swing arm. Because of what I had planned for this carrier, DOM tube for the swing arm was not going to be stong enough to resist the twisting force that Krawler was going to exert (in my opinion), so I came up with this idea of using 2x4x3/16" square tube for the swing arm, and a 1 3/4" DOM tube extension to mount the latch mechanism. I ground the tube to fit snugly into the swing arm stock and plug welded it into place.
Time to get out the bender for a work out. First, I bent the main hoop. My intent was to get the tire up out of my departure angle, and mount it as tight to the back of the rig as I could. I picked up a couple of 1 3/4" bushings from Poly as well to allow the hoop to swing down. Here is the result:
After getting the hoop where I wanted it, I began building out the rest of the swing arm. I thought through several options on the attachment point to latch the swing down portion of the carrier to the static part of the swing arm. Ultimately I came up with what I thought was a very simple solution (anyone know Occam's Razor?). Using the T-Bar and the associated screw tube from my old OR Fab carrier, this is the design I landed on. When swung up into the upright position, ultimately with the tire attached, the T-bar passes through a tube attached to the swing down portion, and screws down to the upright on the swing away. This tube, and the T-bar inside, pass through the center hole on the spare (other pictures later will show this more clearly).
Here are a few pics with the tire mounted. One nice thing I found with the screw down design is that I could size the carrier so that it sqeezes the tire just a bit when mounted, keeping everything tight and rattle free.
Now I began working on the tire mount for the swing down. You can't see it very well in the pictures, but I built a round mount out of 3/8" plate with a 1 3/4" hole in the center. This went around the tube mounted perpendicular to the swing down (through which the T-bar passes to the screw), and then added gussets to firm it all up.
My old tire carrier had a great location for the high-lift, and I built a similar mount here. Because the holes in the main bar of the high-lift are elongated, it always irritated me that it was tough to get the jack to mount straight. Another simple solution I came up with was to make a couple of square washers which fit into the slot surrounding the holes, and the jack centers just by tightening down the wing nuts. OK, so this one was not exactly rocket science...