When it comes to detecting wheel-end problems, it pays to take a closer look at the bearings, say the experts at Timken. Careful observation can reveal early signs and symptoms of wheel-end problems before bearings are damaged and need to be replaced. With prompt inspection and maintenance, fleets can reduce bearing damage in conventional wheel ends and save on long-term costs.
Begin with a simple walk-around wheel inspection—bearing damage may have already begun if you notice:
• Hub cap sight glass that is discolored or burnt
• Low lube level in a hub cap sight glass
• Lube leakage on any external surface of a wheel hub or tire, both inboard and outboard sides—this can appear as a lube swirl or spiral pattern on a hub or tire surface.
• Abnormal tire wear
• Smoking or extremely hot hub cap (too hot to touch)
An alert driver also can detect early-stage problems. Bearing damage may have already begun if the driver notices:
• Wheel vibration
• Wheel wobble
• Wheel noise
• Smoke from a wheel-end
• Increased stopping distance or decreased braking power
• Increased fuel consumption
• Abnormal side pull when brakes are applied
• Wheel lock-up or skidding
Bearings must be replaced if you observe:
• Dry, caked lube in the hub caps or other internal cavity
• Metal particles in lube, hub caps, hubs or bearings
• Head discoloration on the bearings or other internal components.
• Evidence of cups or cones spinning or turning
• Visual wear on any other bearing surface
• Dents on the cage of the bearing assembly
• Spalling (flaking away) of bearing material on races of roller bodies
• Any raised metal or dents on the rollers or races
Timken warns that failure to replace a bearing under these circumstances can result in wheel separation, creating a risk of serious bodily injury. For more information, visit www.timken.com.
