Identifying HD Wheel End Problems

Regular inspection and maintenance can reduce bearing damage in conventional wheel ends and decrease long-term costs.

Visual Wheel Inspection

Visual Wheel Inspection

Bearing damage indicators:

  • Low lube level in hubcap sight glass
  • Hubcap sight glass discolored or burnt
  • Lube leakage on wheel hub or tire, inboard and outboard sides
  • Abnormal tire wear
  • Smoking or extremely hot hubcap

Driver Observations

Bearing damage indicators:

  • Wheel vibration
  • Wheel wobble
  • Wheel noise
  • Smoke from a wheel end
  • Decreased braking power
  • Increased fuel consumption
  • Abnormal side pull when braking
  • Wheel lock-up/skidding

Wheel End Disassembly Analysis

Bearings may need replaced:

  • Worn nut face (adjusting nut and lug nuts)
  • Bearing noisy when rotated
  • Rust or moisture
  • Spindle wear (more wear on bottom half)
  • Hub shoulder wear
  • Thread wear
  • Hub bore wear
  • Loss of adjusting nut or jam nut torque
  • Bearing dropped
  • Worn out or damaged seals

Bearings must be replaced:

  • Dry, caked lube in hubcaps or other internal cavity
  • Metal particles in lube, hubcaps, hubs, or bearings
  • Heat discoloration on bearings or any other internal component (heat discoloration is a nonremovable stain)
  • Wear on any bearing surface•Grooves on bearing cone (inner race) backface, bore or spindle
  • Dents on bearing assembly cage
  • Spalling (flaking away) of bearing material on races or roller bodies (Fig. 1 and 2)
  • Any raised metal or dents on races or rollers 
WARNING Failure to observe the following warnings could create a risk of death or serious injury.

Proper maintenance and handling procedures are critical. Always follow installation instructions and maintain proper lubrication. Never spin a bearing with compressed air. The rollers may be forcefully expelled.

Skill Level: Easy to Difficult | Special Tools: None 

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