GEAR TOOTH CONTACT PATTERNS
GENERAL INFORMATION
Gear Tooth Contact Patterns
* PLEASE READ THIS FIRST *
The following article is for GENERAL INFORMATION purposes
only. Information does not SPECIFICALLY apply to all years, makes and
models, but is to be used as a general reference guide.
INSPECTION
PRELIMINARY INSPECTION
Wipe lubricant from internal parts. Rotate gears and inspect
for wear or damage. Mount dial indicator to housing, and check
backlash at several points around ring gear. Backlash must be within
specifications at all points. If no defects are found, check gear
tooth contact pattern.
GEAR TOOTH CONTACT PATTERN
NOTE: Drive pattern should be well centered on ring gear teeth.
Coast pattern should be centered, but may be slightly toward
toe of ring gear teeth.
1) Paint ring gear teeth with marking compound. Wrap cloth or
rope around drive pinion flange to act as brake. Rotate ring gear
until clear tooth contact pattern is obtained.
2) Contact pattern will indicate whether correct pinion
bearing mounting shim has been installed and if drive gear backlash
has been set properly. Backlash between drive gear and pinion must be
maintained within specified limits, until correct tooth pattern is
obtained.