TRUCK SERVICE MANUAL
AXLE-REAR
A high contact indicates pinion is
The actual back lash changes approximately .008" for
to far out. Set the pinion to the correct
each .010" movement of the gear.
depth by removing shims under the
pinion cage. Slight outward movement
CORRECT TOOTH CONTACT ASSURES LONGER
of hypoid gear may be necessary t
GEAR LIFE
maintain correct backlash.
With adjustments properly made (pinion at correct depth
and backlash set at .010") the following contacts will be
procured. The area of contact favors the toe and is centered
between the top and bottom of the tooth.
SATISFACTORY TOOTH CONTACT (GEARS
UNLOADED)
A low contact indicates pinion is
The hand rolled pattern shown above (gears unloaded)
to deep. Set the pinion to the correct
will result in a pattern centered in the length of the tooth when
depth by adding shims under the pinion
the gears are under load. The loaded pattern will be almost full
cage. Slight inward movement of the
length and the top of pattern will approach the top of the gear.
hypoid gear may be necessary t
(Shown Below)
maintain correct backlash.
A high backlash setting can be used to keep the contact
from starting too close to the toe, and a low backlash setting
can be used to keep the contact from starting too far away
from the toe.t
t For further detailed information refer to SAE Paper SP228,
The pattern of the coast side of
Section 2 by W. A. Johnson and R. F. Cornish.
teeth will appear the same width as the
drive side shown above; however, the
overall length will be centered between
the toe and heel of gear tooth.
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