Spicer Ring and Pinion Tooth Contact Pattern Information - Manual (Page 2)

2
SHAIS168B – Ring and Pinion Contact Pattern Information
Incorrect Pattern - Adjust Backlash
If the contact pattern shows incorrect tooth depth contact, change drive pinion position by altering the shim
pack. Used gearing should achieve proper contact with the same shims removed form the axle at disassembly.
Always recheck backlash after shim changes.
Pattern to close to
tooth top land and
off center.
Pattern to close to
tooth root.
Remove Shim
Add Shim
Pattern is running
off the toe of the
tooth.
Increase Backlash
Decrease Backlash
Pattern is more
than 3/8” off the
toe of tooth.
Increase backlash by loosening the bearing adjuster on the tooth side of the ring gear several notches.
Loosen the opposite adjuster one notch. Return to adjuster on the tooth side of the ring gear and tighten adjuster
until it contacts the bearing cup. Continue tightening the same adjuster 2 or 3 notches. Recheck backlash.
Decrease Backlash by loosening the bearing adjuster on the tooth side of the ring gear several notches.
Tighten the opposite adjuster one notch. Return the adjuster on the tooth side of the gear and tighten adjuster
until it contacts the bearing cup. Continue tightening the same adjuster 2 to 3 notches. Recheck backlash.
If necessary, adjust the contact pattern by moving the ring gear or drive pinion. Ring gear position
controls the backlash. This adjustment moves the pattern along the face width or up and down the
gear tooth. Pinion position is determined by the size of the shims behind the pinion bearing cage,
and controls tooth depth contact.
These adjustments are interrelated. As a result, they must be considered together even though
the pattern is altered by two distinct operations. When making adjustments, first adjust the pinion,
then the backlash.
Incorrect Pattern - Adjust Pinion Position