Inspection of the Wheel End, Rear Axle

sd mm 35.04.001
  1. Park the vehicle on a level surface, shut down the engine, set the parking brake, and chock the tires.

    2. Warning: Never work around or under a vehicle that is supported only by a jack. Always support the vehicle with safety stands. Jacks can slip, causing the vehicle to fall, which could result in serious injury or death.

  2. Raise the rear of the vehicle until the tires clear the ground. Then place safety stands under the axle.
  3. Remove the rear wheel and tire assemblies. For instructions, see  of the 108SD and 114SD Workshop Manual.
  4. Remove the brake drum. For more information, see  of the 108SD and 114SD Workshop Manual.
  5. Check for loose, damaged, or missing fasteners.
  6. Check for lubricant at the wheel seal and drive flange gasket. If lubricant is present, investigate the cause and take corrective action.
  7. Check for lubricant around the hub, brake hardware, and brake shoes (if installed). If lubricant is present, check the oil seal and replace it as necessary. For instructions, see Section 35.02 of the 108SD and 114SD Workshop Manual .
  8. Remove the axle shaft.
  9. Inspect the lubricant for discoloration. Under normal conditions, the lubricant will darken; a white or milky appearance indicates water contamination. If the lubricant is discolored, service the wheel end. See the 108SD and 114SD Workshop Manual and manufacturer literature for procedures.

    10. Important: Do not mix different types of lubricants.

  10. Inspect the lubricant for the presence of foreign matter. Use a magnet to detect any metallic materials present in the lubricant. If the lubricant is contaminated, service the hub. See the 108SD and 114SD Workshop Manual and manufacturer literature for procedures.
  11. Rotate the hub and check for free, smooth, and quiet rotation. If rotation is hampered or rough, or any unusual noise is heard, service the hub immediately. See the 108SD and 114SD Workshop Manual and manufacturer literature for procedures.

    12. Warning: Correct wheel-bearing end play is crucial to the safe and sound operation of the vehicle. If the end play is not correct, the wheel bearings could fail and cause the loss of the wheel and hub assembly and result in an accident causing property damage, serious injury, or death. Use a dial indicator to measure the end play.

    Note: Do not measure the wheel bearing end play with the wheel mounted on the hub; you cannot accurately measure or adjust bearing end play with the wheel mounted on the hub. Also, ensure that the brakes are not applied so that that drum and hub can move freely.

  12. Using a dial indicator, measure the end play as follows.
    1. Attach the magnetic base of a dial indicator to the spindle, and place the measuring end of the indicator squarely against the flange as shown in Fig..

      2. Important: Maintain continual pressure on the hub until you have taken both the inboard and outboard measurements. If you release the hub, an accurate measurement is not possible.

    2. To seat the bearings, grip the hub at the three o'clock and nine o'clock positions, and push inward while oscillating it approximately 45 degrees. Maintain pressure on the hub, note the inboard measurement, and then pull the hub outward while oscillating it as before. Maintain pressure on the hub, and note the outboard measurement.

      The end play is the difference between the two measurements. The end play limit for PreSet hubs is 0.006 inch (0.15 mm); for non-PreSet hubs the acceptable range is 0.001 to 0.005 inch (0.03 to 0.13 mm) inclusive.

      If the end play does not exceed the limit and no other problems were found in the previous steps, no additional service is necessary. If the end play exceeds the limit, service the hub. See the 108SD and 114SD Workshop Manual and manufacturer literature for procedures.

      1. Dial Indicator (with magnetic base)

      2. Axle Shaft Mounting Flange

      Fig. 1, Dial Indicator Setup

Note:
Parent topic: Rear Axle
Document Number: 0000120033
Manual Publication Date: 2024-05-23
Topic Publication Date: 2024-10-30