Follow along as Michael Finch, a Suspension Specialist at 4Wheel Drive Hardware, builds this Cheap Cherokee project with all the preventive maintenance required and a number of choice, but economical, upgrades. Once complete, his teenage daughter will be able to drive to school and dance practice in something reliable, inexpensive and safe — and Michael can teach her off-roading. If you missed them, check out the Introduction to this project along with the Front Suspension and Rear Suspension installations.
Bring on the Meats
Now that the XJ is lifted, we needed wheels and tires. With all the options out there it’s easy to lose your perspective. The biggest thing in my mind and for this project is bang for the buck. This is a daily driver and will occasionally see sand, snow and rocks. With these varied conditions slightly more skewed to street, I decided to go with all-terrain (AT) tires. Given the price and the mileage guarantee, the Pro Comp Xtreme AT was our best choice. I was looking at the MT2 Mud Terrains as well, but the AT’s tighter lug pattern, yet still aggressive sidewall seemed like it would be better for quieter highway driving in the long run. With a 50,000 mile tread wear warranty and the extreme warranty available, how can you go wrong?
For the wheels, I chose the Pro Comp steel wheels in a 15″ x 10″ with 3.75″ back spacing. This will probably not make the CHP very happy because it will cause the 12″ wide tires to stick out a bit from the fender flares, but it won’t be the first time I’ve gotten a mud flap ticket. With the tire and wheel tab coming to over $1,000, I’m looking to save any extra pennies I can. For 33×12.5×15 tires with rims, that’s not a bad deal.
DIY Mounting
So, to stick with the save pennies idea, I decided to mount the tires myself. Just to be clear, this isn’t the first time I’ve done this. I put a set of 35-inch MT/Rs on 15-inch rims using the same setup. So, off to Harbor Freight to pick up a $40 tire machine. I use the word “machine” lightly. With new tires it can be a real pain to mount them. Used tires where the sidewall and the bead are more flexible are quite a bit easier. It will make it go a lot easier if you leave them in the sun and let the rubber get nice and warm.
Here’s how you do it. Set up your tire machine. I recommend bolting the machine down to a concrete pad, but in a pinch, you can bolt it to a pallet like we did. Next, mount a rim on the machine with the valve stem hole on the top side. Install a new valve stem into the rim using a generous amount of lube. Soap or soapy water works fairly well. WD-40 also works great, but is a little hard on the rubber.
The Pro Comp ATs are directional, so make sure you have two set up for the left and two for the right. There’s an arrow on the side of the tire that shows the direction of rotation. You need to match the “dot” on the tire to the valve stem hole on the rim. The dot should be red or yellow. Put the tire on the rim with half of the bead below the rim lip. Use the tools provided with the tire machine and maybe a pry bar or two to work the back bead over the outside bead lip. Now comes the hard part: getting the outside bead over the outer rim lip. Same as the back bead, push one side of the bead below the rim lip. Using one tool, pin the tire to the rim and work the bead over the rim using the other tool.
Dynamic Balancing
Now you’re asking, “Okay, so you got the tires on the rims, now how are you going to balance them?” Here’s the problem with balancing aggressive or large lug tires: they don’t. If you do get them balanced, they won’t stay that way long. The reasons for this are that the tires are losing a lot of rubber and you’re likely going to use them off-road at low pressure.
Even with a 50,000 mile warranty, the tires are going to shed weight over time, anyone that’s seen a well-worn mud terrain tire knows this is true. Also, because these are off-road tires, you know you’re going to air down at some point. When you air down, you’ll most likely either lose a rim weight or the tire will slip on the rim. Without the bead pressing against the rim at street pressure, the wheel weights can be easily knocked off or simply fall off and the rim can spin inside the tire destroying any static balancing. The adhesive weights on the inside of the rim work well and are less likely to get lost, but there’s still the issue of the tire spinning on the rim. Either way you go, static balancing almost guarantees that the balance will change after every trip and can even drift out of balance with regular street use.
My solution is dynamic balancing. This means you have a medium in the tire that will move inside the tire to balance the tire every time you drive. Wondering how this is possible? The simple explanation is that the rotation of the tire causes the loose material to naturally settle at the spots that need additional weight and any excess distributes evenly, creating a dynamically balanced tire with no vibration. People have been using sand, lead shot and even some liquids to balance tires in this way. My personal choice is airsoft pellets. There are two weights – choose the heaviest. It takes roughly 1,000 airsoft pellets per tire up to 35s.
Pellets, Pellets Everywhere
Now for the airsoft pellets. The easiest way to get the correct numbers is to find a 5,000 round box of .20 gram pellets. Split the tub of pellets between four cups as evenly as possible, but without counting pellets. This will give you about 1,250 pellets per cup. After checking that the back bead is tight on the rim, push down on the front sidewall of the tire to create a gap between the bead and the rim and this will give you room to pour in the pellets. Check to see that all the pellets are in the tire and that none are stuck in the bead.
For this next part, you will need a good source of compressed air. The small hook-to-your-battery compressors will probably not do it. An air compressor that’s set to 80 PSI will get the job done. Without using the air chuck, push the end of the air hose directly onto the tire stem. This will give you the maximum amount of air into the tire core and “set” the bead. If you hear air leaking, you might need to muscle the tire around on the rim to get the bead to capture. In a worst-case scenario, take a ratchet strap and wrap it around the tread. As you tighten the strap, the bead will push up on the rim, sealing it. As soon as the air starts to fill the tire it will seat on the bead. You’ll hear a “pop” as the bead seats.
Set your tire pressure and mount your tires and you’re good to go. When you slow down you’ll hear the pellets drop out and ping against the rim — you now have four of your very own rain sticks.
The next installments will look at some additional parts that will take this kit from fire road cooker to rock crawling monkey. Axles and body armor coming soon.
Be sure to check out 4WD for all your XJ Jeep parts needs.