WHEELS, RIMS AND TIRES
WHEEL BEARING SEAL AND BEARING CAP DIAGNOSTIC CHART
Prior to replacing a leaking wheel seal or front wheel hub cap, the actual cause of the leakage should be diagnosed to
insure that the leakage problem will not reoccur.
You will note that the chart has four categories where the leakage could occur; do not overlook all four situations.
Possible contributory causes of apparent wheel seal leakage are:
CAUSE
CORRECTION
WHEEL SEAL
Seal Cocked or Not Properly Seated in
Hub
Be sure to confirm uniform seating of seal after installation. Use
proper installation procedures.
Seal Lip Cut or Rough on Open Lip
Type Seals. Inside and Outside
Diameter Damaged on Unitized Seals
New seal could have been damaged prior to installation. Inspect
lips of new seals before and after installation in hub. Seal can also
be damaged due to abuse during installation of hub assembly by
contact with spindle or axle end or threads.
Worn or Damaged Wiper Ring and Seal
Normal wear of seal lip to wiper ring contact area or improper
installation of wiper ring. Replace seal and wiper ring using correct
installation tools.
Seal Loose or Too Tight in Hub Bore or
Seal Lip Over Size
Check for correct application of seal assembly.
Sealant Not Applied to Seal Outside
Diameter When Required
Use Loctite Gasket Eliminator when instructed to do so.
Grease On Inside or Outside Diameter of
Mechanix Barrier Seal
Grease may cause seal to move in hub bore or at axle housing or
spindle. Seal is designed to grip hub bore and axle housing or
spindle. Remove grease from inside and outside diameter.
Brake Cam Shaft Seal Leakage
Excessive lubrication of brake cam shaft can cause grease to enter
brake groups and may be mistaken for faulty wheel seal. Do not
overlubricate brake cam shafts.
GREASE CAP
Lubricant on Exterior of Grease or Hub
Cap
Lubricant spillage either at initial fill or lube added. Steam clean
lubricant from grease cap so that it is not mistaken as a faulty sight
glass, bearing cap or gasket.
Over Fill of Lubricant
Excessive lubricant can cause lube to be expelled from grease cap
plug. Maintain proper fill level mark on window.
CTS-4148A
Page 16
