WHEELS, RIMS AND TIRES
Figure 15. - Oil Lubricated Wheel Seal With Wiper Ring
Figure 16. - Oil Lubricated Wheel Seal and Wiper Ring
With Grit Guard
Unitized Scot or National Seals
Unitized seals (Figure 17) in most installations do not
require axle wiper rings and minimize wear on the axle
spindle as follows. The outer shell of the seal being
pressure fit in the wheel hub rotates with the wheel
around the sealing element which is pressure fit on the
axle spindle. With the unitized seal when replacement is
made, the worn surface created by the sealing lip is also
replaced by virtue of a new seal.
Figure 17. - Unitized Scot or National Seal
Barrier Unitized Seal
The rubber encased seal shown in Figure 18 Is a barrier
type seal. The seal effect is between the lips and
encased metal ring. This type of seal is installed by hand
and should not normally have any lubricant or sealant
added to the inner or outer surfaces when installed.
New seals have a lubricant applied to the mounting
surfaces to aid in the installation. Do not apply grease to
these surfaces. If grease should be applied to the outer
surface of seal, the seal could slip in the hub or on
spindle or axle tube.
CTS-4148A
Page 9
