1. Wheel Bearing Failures

2. Improper Adjustment
RESULT: Large end of rollers & races are worn, galled and spalled.
CAUSE: Internal clearances reduced – tight adjustment, excessive thrust.

3. Improper Adjustment
RESULT: Large end of rollers & races are worn, galled and spalled.
CAUSE: Internal clearances reduced – tight adjustment, excessive thrust.

4. Improper Adjustment
RESULT: Large end of rollers & races are worn, galled and spalled.
CAUSE: Internal clearances reduced – tight adjustment, excessive thrust.

5. Improper Adjustment
RESULT: Small end of rollers & races are worn and spalled.
CAUSE: Loose adjustment.

6. Misalignment RESULT: Angled wear of spalling on races.
CAUSE: Cocked installation, improper ring seating, warped shaft.

7. Misalignment RESULT: Angled wear of spalling on races.
CAUSE: Cocked installation, improper ring seating, warped shaft.

8. Misalignment RESULT: Large end wear opposite small end wear.
CAUSE: Cocked installation, improper ring seating, warped shaft.

9. Misalignment RESULT: Large end wear opposite small end wear.
CAUSE: Cocked installation, improper ring seating, warped shaft.

10. Impact Loading RESULT: Indented races that can progress to spalling.
CAUSE: Impact load during installation or operation.

11. Impact Loading RESULT: Indented races that can progress to spalling.
CAUSE: Impact load during installation or operation.

12. Contaminated Lubricant
RESULT: Indented and bruised races and rolling elements that can progress to spalling.
CAUSE: Hard particles in lubricant.

13. Contaminated Lubricant
RESULT: Indented and bruised races and rolling elements that can progress to spalling.
CAUSE: Hard particles in lubricant.

14. Improper Lubrication RESULT: Frosting.
CAUSE: Oil film too thin to separate rolling elements and races.

15. Improper Lubrication
RESULT: Heat discoloration on rolling elements and races.
CAUSE: Inadequate lubrication.

16. Improper Lubrication RESULT: Catastrophic failure.
CAUSE: Inadequate lubrication.

17. Poor Fit in Bore and on Shaft
RESULT: Localized Spalls.
CAUSE: Unsupported outer ring – irregular housing bore.

18. Poor Fit in Bore and on Shaft
RESULT: Localized Spalls.
CAUSE: Unsupported outer ring – irregular housing bore.

19. Poor Fit in Bore and on Shaft
RESULT: inner ring cracks during installation.
CAUSE: Excessive press fit.

20. Poor Fit in Bore and on Shaft
RESULT: Fretted (corroded) and/or polished ID or OD.
CAUSE: Insufficient press fit on shaft or in bore.

21. Etching
RESULT: Corrosion between rolling elements and races that can progress to spalling.
CAUSE: Moisture.

22. Etching
RESULT: Corrosion between rolling elements and races that can progress to spalling.
CAUSE: Moisture.