They say football is a game of inches; the differential in a vehicle is a matter of millimeters. Specialty tools, experience, and a Dodge maintenance manual are all necessities if you're planning to rebuild an axle on a Dodge pickup truck. Differentials use a set of gears to transfer power from the motor to to the wheels. Each differential uses factory specifications known as backlash, pinion depth, and preload that are unique to each axle.
Several specialty tools are needed to complete this installation. A hub puller removes the outer pieces of the axle. Also, an oversized specialty socket may be necessary to remove the nut that holds the hub to the axle housing. This will depend on the year and model of the truck. Once the outer pieces of the axle have been removed, a good socket set will be needed to remove the differential cover as well as the carrier bearings. When you start the installation process, use a micrometer to measure shims for the carrier. Also use an inch-lb. and foot-lb. dial indicator for measuring the forces of torque on a bolt.
The ring and pinion consist of interlocking teeth on a metal body, whether it be the pinion with a shaft or the gear ring. The ring and pinion are joined by a carrier housing that the gear ring is bolted into. This carrier spins as torque is applied to the ring teeth. Shims are needed for getting the correct position of the ring gear and pinion. Millimeters can make the difference between catastrophe and flawless function. You can purchase individual shims or find an axle-specific install kit that comes with new shims and bearings, ring bolts, thread lock, crush sleeve, and gear paint. The ring and pinion must be purchased separately.
Clean the axle housing thoroughly after it has been disassembled. Brake cleaner and degreaser are cleaning agents recommended for this step. Clean out any residue left by the cleaners before starting the installation. The installation process takes several tries to be sure that the best fit has been achieved. Everything needs to be removed from the axle included bearings, knuckles, and seals.
Since the axle is out of the vehicle and apart, now is the time to install new parts. Replace the old bearings with new ones and all the old seals with fresh ones. With the bearings in place, insert the pinion and carrier with the ring gear into the axle. Check the pattern on the gears by painting them with gear paint and turning them by hand. This is where the shims come into play. Shims are thin pieces of metal used as spacers to make minimal adjustments. Each ring and pinion have their own settings for shims because no two sets are alike. Bolt down the carrier housing once the ring and pinion are set up to the proper depth. Reassembly of the axle is the final process of the gear swap and then the axle can be reinstalled under the Dodge truck.
