Jeep Wrangler TJ Axle Swapping On The Cheap - 4-Wheel & Off-Road Magazine

Ali Mansour Brand Manager, 4WD & Sport Utility

Out of-the-box the ’97-’06 Jeep Wrangler TJ is an extremely well-performing off-road machine. Add a small lift, lockers, and knobby tires and it will take you far. Unfortunately, many of the open-top wheelers have a ticking time bomb of a rear axle, known as the Dana 35. In the stock configuration the 71⁄2-inch ring gear and 28-spline C-clip axleshafts on the Dana 35 are adequate at best. When you add big tires and tough terrain into the mix the light-duty diff just can’t keep up. So what’s a wheeler to do?

jeep Axle Swapping On The Cheap welding A Ford 8 8 Axle Photo 36153937

We understand that not everyone can drop the coin on a super-high-zoot aftermarket rear axle, so instead of heading to the bank we suggest heading to the boneyard. Dollar for dollar the 8.8-inch rear axle found under the rear of most Ford Explorers is one of the cheapest and toughest axles you can put under the rear of your Jeep. These junkyard jewels are already fitted with disc brakes (’95 and newer), the same 5-on-41⁄2 wheel bolt pattern, 31-spline axleshafts, and an 8.8-inch low-pinion gearset. On top of having stronger internals, the 8.8 housing is designed to carry more weight than the Dana 35. This makes it great for holding up the lightweight TJ platform, and when used with restraint it can live a long life turning up to a 37-inch-tall tire.

To find out what it takes to put one of these junkyard jewels into the back of a Wrangler, we took a trip to the gear and 8.8 experts at East Coast Gear Supply in Raleigh, North Carolina. East Coast Gear Supply specializes in the 8.8 conversion for XJ, TJ, and YJ Jeeps and has years of drivetrain experience. In addition to selling complete bolt-in axles, ECGS offers a host of in-house axle brackets, brake, and yoke parts for the DIY 8.8 axle builder. For more information check them out on the web at www.eastcoastgearsupply.com.

Builder Notes
While the 8.8 swap may seem a little labor intensive, it’s definitely something you could knock out over the weekend with the proper skills and tools. The factory Dana 35 TJ rear axle is roughly an inch wider than the 8.8. Most Wranglers running aftermarket wheels with around 31⁄2 inches of backspacing should be fine. Rigs with factory wheels or less wheel offset should plan on running a set of wheel spacers.

jeep Axle Swapping On The Cheap completed Ford 8 8 Axle Photo 35960593

Another item to note is that the yoke offset on the 8.8 is 2.75 compared to the Dana 35’s 0.75. This means your driveline will be slightly angled. For those equipped with a slip-yoke eliminator and CV driveline this will not be noticeable. If your Jeep is still fitted with the factory driveline and slip-shaft you will likely encounter a driveline vibration.

PhotosView Slideshow Depending on the type of boneyard, the 8.8 donor axle will already be removed or you’ll be plucking it out from under the Explorer yourself. The ’95-and-newer Explorers are fitted with disc brakes, so they are the most desirable. When buying any used or salvaged axle always make sure that most of the necessary components are there, and examine the axle closely to make sure that it’s not bent or tweaked. The Explorer leaf spring mounts and shock tabs will need to be zapped off of the axle. A plasma cutter or cutting torch will make this part easy. If you don’t have access to either of those, a grinder and a cutoff wheel can get the job done as well. Once the original brackets are removed take a grinder with a flap disc and clean the axletubes thoroughly. Since you’ll be welding on new brackets it’s imperative that you start with a clean surface. A little prep time saves a lot of headaches later. The first bit of welding that East Coast Gear Supply suggests is welding the axletubes to the housing. The 8.8 tubes have been known to twist and break free from the differential housing. Welding the tubes adds that extra bit of protection. To ensure that each 8.8 TJ conversion rear axle is alike, ECGS uses an axle jig to fix each axle. If you’re ordering your axle direct, ECGS can adjust the brackets and pinion angle to cater to your Jeep’s lift height and build configuration. The heart of the 8.8 conversion is the East Coast Gear Supply axle bracket kit. Each kit is comprised of 1⁄4-inch steel brackets that include a heavy-duty adjustable track bar, bolt-on coil retainers, and longer shock tabs to keep the shocks from contact the axle tubes. The TJ specific axle bracket kit also comes with detailed instructions to guide you through the conversion process. If you’re doing the swap in your garage we suggest lining up your factory Dana 35 axle in front of the 8.8. This will give you center points to measure from so you can double-check your bracket placement. New bearings are a must on just about any junkyard axle. The 8.8 wheel bearing and seal assembly simply tap in from each axle end. Plan on replacing the parking brake pads as well, as we’ve found most are brittle and beyond use. One aspect of the 8.8 that we’re not huge fans of is the C-clip axle retainer. The C-clip is what holds your axleshaft in place and is a common failing point in general on virtually all C-clip axles. There are C-clip eliminator kits available from the aftermarket. ECGS also offers an in-house upgrade that deletes the C-clip and replaces the housing ends with a larger set 20 bearing similar to what’s found on the Ford 9-inch. To mate your TJ’s driveline up to the new housing, you’ll either need the adapter flange or the 1310 replacement yoke Larger yoke sizes are also available for those looking to go a little bigger. ECGS suggests that you upgrade your yoke at the same time you change your gearset, as the 8.8 uses a crush collar to set the pinion. Since the 8.8 is a low-pinion housing it rides on the stronger drive side of the ring gear. At the factory, Ford equipped the Explorer with 3.55, 3.73, and 4.10 gearsets. There is a chance that you might score with a 4.10 limited-slip rear axle, but we’d still plan on ditching the factory gearset and bearings just for peace of mind. The Explore rear disc usually needs a good refresh, but will clear a 15-inch wheel without issue. ECGS offers a DOT soft and hard line kit along with the correct e-brake cables to finish out the braking system. The copper-nickel soft line is extremely corrosion resistant and can be hand-bent to maneuver around the axle’s brackets. One spot that is prone for leaking is the 8.8’s ABS sensor plug. Since the ABS sensor is unused on the TJ, ECGS offers an inexpensive freeze plug upgrade that simply taps in place of the OE sensor.