Stemco’s product manager for engineered products, Vincent Purvis, said that in addition to TMC’s RP618A, “Wheel Bearing Adjustment Procedures,” fleets should also consider proper lubrication of wheel end bearings and systems as referenced in TMC’s RP631B. He highlighted the use of Stemco’s Pro-Torq or Zip-Torq nut to ensure proper wheel end play, and recommended the following steps:
- Remove keeper from nut.
- Seat the bearing by tightening the Pro-Torq or Zip-Torq nut on to the axle to 200 ft./lbs. three times while spinning the hub. Then back off the nut until it is loose.
- Adjust the bearing by tightening the Pro-Torq or Zip-Torq nut on to the axle to 100 ft./lbs. three times while spinning the hub. Then back off the nut one face mark.
- If installing the Pro-Torq nut, insert the keeper into the undercut groove of the nut and engage the keyway tang in the axle keyway. Then insert the keeper tab with the orange side facing out. Engage the mating teeth and compress and insert the keeper arms, one at a time, into the undercut groove using a screwdriver.
- Inspect the installation to ensure that the axle fastener is properly installed and that the keeper is fully seated into the undercut groove.
- Measure wheel end play with a dial indicator to ensure the axle fastener is within the recommended wheel end play of 0.001 to 0.005 in.
