Nissan began offering the Pathfinder with automatically locking hubs in 1984. Four-wheel drive enthusiasts no longer had to get out to lock and unlock their hubs as they passed over difficult terrain. The automatic locking hub runs freely when the four-wheel drive is disengaged, reducing wear in the front hub and increasing fuel mileage. When the four-wheel drive is engaged, a pair of brakes engage inside the hub, locking it to the drive shaft. The outer brake is referred to as "Brake A", and the inner one is "Brake B."
Loosen the front wheel nuts, jack up the vehicle and lower it onto jack stands.
Remove the six hub-assembly bolts, using the Toryx wrench. Keep a pan or cloth beside you to lay out the parts in order as you remove them. Replacing in the same order is critical to this repair job and it is easy to get them mixed up.
Pull the hub off slowly. Grab the O-ring, spring and "Brake A" as the hub comes off. Lay them in order on the pan or cloth you have beside you.
Use the snap-ring tool to remove the snap ring; then remove the two washers that follow and "Brake B." Lay them down in order.
Install the hub assembly with new components in the exact reverse order as the removal. You can refer to the parts you have laid out beside you. Start with "Brake B," followed by the two washers. The new hub assembly will have instructions on which components to grease as you install them.
Use the snap-ring pliers to install the snap ring. Follow with "Brake A," the spring and the O-ring.
Install the hub on the shaft, followed by the six hub bolts. Tighten the hub bolts with the Toryx wrench.
Install the wheel and tire assembly on the lug bolts and hand-tighten the lug nuts. Lower the vehicle and tighten the lug nuts with the lug wrench.
