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Tooth Contact Pattern Check - Gearset, Dana S135

Tooth Contact Pattern Check - Gearset, Dana S135

1. CAUTION: If reusing the differential ring gear and pinion, measure and record the backlash before disassembly. Re-assembling the differential ring gear and pinion to the recorded backlash will match the established wear patterns. Hand rolled patterns will cover less area than the established patterns.

Paint one quarter of both the drive and the coast side of the differential ring gear with marking compound.

2. While applying a load, rotate the differential ring gear one complete revolution.

Correct Contact Pattern - Single Index Lightly Loaded:





Correct Contact Pattern - Single Index Heavily Loaded:






3. Verify the contact pattern is correct.
- Tooth contact pattern can move only by adjusting backlash. Tooth contact pattern can move only in the direction of heel-to-toe, and toe-to-heel. Depth of the tooth contact pattern is not adjustable. Contact Spicer Service at 1-800-666-8688 for assistance if you are unable to establish an acceptable tooth contact pattern within the limits of backlash.