Chevrolet Blazer/Jimmy 1969-1982 Repair Guide

Locking Hub



Locking hubs were optional through 1974 with conventional four wheel drive, and standard equipment for 1975 and later.

Locking hubs may not be used with full time four wheel drive. See this section, under Transfer Case, for details. Locking hubs should be run in the lock position for at least 10 miles each month to assure proper differential lubrication.

This procedure requires snapring pliers and a special hub nut wrench. It isn't very easy without them. You will have to modify this procedure if you have non-factory installed hubs.

  1. Set the hub in the Lock position.
  3. Remove the outer retaining plate allen head bolts and take off the plate, O-ring, and knob.
  5. Take out the large snapring inside the hub and remove the outer clutch retaining ring and actuating cam body.
  7. Relieve pressure on the axle shaft snapring and remove it.
  9. Take out the axle shaft sleeve and clutch ring assembly and the inner clutch ring and bushing assembly. Remove the spring and retainer plate.
  11. Clean all the hub components in a safe solvent and dry them. Lubricate everything with a high temperature grease.

To install:

  1. Install the spring retainer plate with the flange side to the bearing and seat it against the outer bearing cup.
  3. Install the spring with the large end against the retainer plate.

When the spring is properly installed and seated it will extend past the spindle nuts about 7 / 8 inch.

  1. Place the inner clutch ring and bushing assembly into the axle shaft sleeve and clutch ring assembly. Install these components, push in, and install the axle shaft snapring. If there are two axle shaft snapring grooves, use the inner one.

You can install a 7 / 8 16 inch bolt in the axle and pull out to aid in seating the snapring.

  1. Install the actuating cam body with the cams out. Replace the outer clutch retaining ring and then the internal snapring.
  3. Install a new O-ring, then install the actuating knob and retaining plate in the lock position. The grooves in the knob must fit into the actuator cam body. Install the cover bolts and seals.