No Lift 1998 Jeep Wrangler TJ 35 Inch Tires Fitting - Part 1Posted in Project Vehicles on July 17, 2006 Comment (0)
Adding a lift to your Jeep has plenty of benefits. More space between your fenders and tires means you have room for bigger tires. Bigger tires will give you a few more inches of air between your axles, transfer case (as well as other vitals), and the dangers of the trail below. Sounds good, right? Well, not exactly. Oftentimes these added benefits are weakened by the unexpected side effects that come from your new lift. You've changed the geometry of all your suspension, steering, and driveline components, not to mention making your Jeep less stable by raising the center of gravity. If left unaddressed, these changes can lead to problems like bumpsteer, loss of traction-adding antisquat in your rear suspension, and vibrations from your maxed-out rear driveshaft.
Most Jeep owners put up with these problems because, to them, the benefits of bigger tires outweigh the undesirable side effects. But the truth is, you don't have to deal with these side effects. In fact, you don't have to lift your TJ at all in order to get bigger tires on it. We were able to fit a set of 35x13.50-15 Mickey Thompson Baja Claws on an unlifted '98 TJ with stock springs, shocks, driveline, and steering. To do this we did some minor sheetmetal trimming, added in some trick mail-order parts, did a pinch of fabrication, and replaced the factory hood and front fenders. The end result is a sleeper TJ with big tires that drives almost like stock on-road and performs awesomely off-road. Here's how we took a stock TJ and tweaked it into a low-CG (center of gravity), rock-hugging Jeep. In Part I of this story we'll show you how we made room for the 35-inch tires on the front of our little TJ. In the next issue we will discuss tire choice and how we got the other pair of 35-inch meats under the rear of our Wrangler. Then we'll take it wheeling.
Starting At Stock
After bolting on a spare set of 31s we had lying around, we took the '98 Wrangler out to see how it would flex. The 31-inch tires are about the biggest we would be comfortable wheeling with on a stock TJ. Any larger and you may get wrinkled front fenders and flares lying on the side of the trail from tire contact. After a lot of measuring and excess tire spinning, we figured that there was about 4 inches of uptravel on the front suspension of our stock TJ and about 512 inches of uptravel in the rear with the sway bars in place. The 31s were practically touching the fender flares both front and rear at full flex, so we knew at the end of our testing we would need to make major changes to get some serious tires under the Jeep sans lift. Fitting 35s at this point seemed impossible.
Making Room For Meat Up Front
Getting big tires under the front of a TJ is as easy as making more room for them. The problem is that making more room for tires on the front of a TJ is not necessarily easy, but there are a few ways we've seen it done. First, we could have just flatfendered our stock TJ fenders or added some trick tube fenders for the same benefits but with added trail-bashing strength. Both of these changes may have given us a few more inches of clearance for maybe 32- or 33-inch tires on the front of the Jeep, but that wasn't big enough for us. We wanted to run 35s.
Our next idea involved dropping the stock fenders altogether: This would give us lots of room behind the tire and more room over the top of the tire. But we doubted even the most Jeep-friendly officer would let open front wheels slide by without notice, and if our measurements were correct, 35s at full flex would still probably make contact with the hood, not to mention make our Jeep look like crap. No good.
Finally we found the answer: The Rock Crawler Hood built by 4 Wheelers Supply and Campbell Enterprises for TJs, CJs, and YJs. This hood is a fiberglass replacement hood with high-clearance miniature fenders molded right in. By combining the fiberglass hood with the supplied steel triangle fenderettes and a bit of fabrication, we would end up with a Wrangler with much more front-tire clearance. Also, the Jeep would still have the all-important front fenders to keep the cops off our backs.
After a quick call to 4 Wheelers Supply in Phoenix, Arizona, our hood was on its way, and we began tearing our TJ apart. The first thing you'll notice after opening a TJ's hood is that the inner fenders do more than just deflect mud and water away from your engine. They also hold many important gadgets like the battery, fuse block, windshield-wiper reservoir, vacuum canister, charcoal canister, and air-intake box. All of these goodies are going to have to be relocated and firmly mounted to the Jeep's frame.
To do this, we built a series of brackets assembled with some square tubing, plate steel, drills and taps, a grinder, our Hobart 175 MIG welder, and a few of the bolts that came off the stock fenders. There are hundreds of ways you could relocate these parts. We did so by first building a baseplate out of steel for the component, then welding this to a piece of tubing which extends down to the frame or the shock/spring tower where a piece of plate steel could be bolted on. By bolting our brackets on, we can easily remove them for service or take them off if we ever want to reinstall the Jeep's factory fenders and hood.
We also had to do something to stabilize the grille, which was pretty shaky once we removed the fenders. To isolate it, and the radiator, we built two small brackets. These brackets use factory holes on the grille and the frame along with two polyurethane bushings. The bushings allow the grille to float independently as the frame flexes and the grille/radiator moves.
Finally, we used some 11/2-inch round DOM tubing to make a stout pedestal that holds a sealed Optima BlueTop Marine battery. This bracket bolts to the frame and the shock tower. It then attaches with a few bolts to our 4 Wheelers Supply battery box, which firmly grabs the battery. This combination of parts allows us to lay the battery on its side and tuck it up and as far under the hood as possible. We also love the deep-cycle BlueTop Optima because you can easily add auxiliary wiring to the two threaded terminals on top. The deep-cycle BlueTops are perfect for high-draw items like off-road lights or winches.
Once the hood and fenderettes arrived at the freight depot, we ran down to pick 'em up. It's important to check the crate for any damage before you accept the hood from the shipper. Oftentimes shipping a large item like a hood can be damaging. The shipping company is responsible for any damage.
To install the new hood, we made a steel template of the factory hood hinge to act as a drill guide on the Rock Crawler hood. Once our new hood was drilled, we laid it on the Jeep and lined up the hinges. We then used some new-grade five bolts, some big-fender washers, and some locknuts to secure the hood to the factory hinges. 4 Wheelers Supply also sent us a set of AutoFab hood pins to hold the Rock Crawler hood closed. We drilled out the holes that hold the Jeep's original spreader bars, which run from the firewall to the grille, and mounted our hood pins there.
KEEPING IT LEGAL (KINDA)
Without the stock fenders in place, our Jeep is now without parking lights or front turn signals. To correct this, we drilled some holes in our grille with a hole saw and added these inexpensive marker lights we found at an 18-wheeler parts store. You can wire these to the factory wires to act as turn signals and parking lights. In the long run, we will add some more lights to the side of the Jeep to replace the running lights that used to be in our factory fender flares.
The last thing we had to address on the front of our TJ was its lack of inner fenderwells. Rainwater, mud, and other road debris could have easy access to our engine and electrical components under the hood. To correct this problem, we ran down to the local hardware store and grabbed some rubber pond-liner material made by Firestone. The flexibility of the rubber sheets allowed us cut pieces to fit into the wheelwells. After installing some soft-top snaps and brass grommets, we were able to zip-tie and snap the rubber in place. Our new Jeep diapers might look funny, but they keep mud out of the engine compartment even better than the stock steel inner fenders. And they are easily removed if we need to clean or get at the engine, computer, or other underhood items.