GMC chervolet camaro 1999 Service Manual page 466

Driveline/Axle
Differential Ring Gear Tooth Nomenclature
The drive side (5) of the differential ring gear tooth
curves outward (convex).
The tooth contact ( 4) of the differential ring gear is the
center area of the drive side (5) that makes the
most physical contact with the pinion gear. Refer to
Effects Of Increasing Load On Tooth Contact Pattern.
The coast side (3) of the differential ring gear tooth
curves inward (concave). ·
The toe end (2) of the. differential ring gear tooth is the
end that is nearest to the center of the. differential
ring gear.
The heel end (1) of the differential ring gear tooth is
the end that is farthest away from the center of
the differential ring gear. The toe end of the tooth is
smaller than the heel end.
Effects Of Increasing Load On Tooth Contact
Pattern
The load on the differential ring and on the drive
pinion gear is increased ·during vehicle acceleration.
An increased load on the differential ring and on
the drive pinion gear may cause the tooth contact (4)
to spread out. Under a very heavy load, the tooth
contact may extend from the near toe to the near heel
on the drive side.
Increasingly heavier loads cause the following changes
in tooth contact:
• The entire contact tends to shift toward the heel
• The entire contact becomes broader with
respect to the tops and the bottoms of the teeth
The following tooth contact pattern test recreates the
effects of a light load. For this reason, the patterns
that
will
be obtained by the following test will only
extend to about half of their potential expansion.
Important: The contact pattern is centrally located up
and down on the face of the differential ring
gear teeth.
The following conditions may cause a change in the
tooth contact pattern under a load:
• A drive pinon gear is insufficiently preloaded
• The differential bearings are insufficiently
preloaded
Rear Drive Axle 4-51
164018