Synchro Ring and Gear Inspection

Inspection





1. Inspect the inside of the synchro ring (A) for wear.





2. Inspect the synchro sleeve teeth and matching teeth on the synchro ring (B) for wear (rounded off).





3. Inspect the synchro sleeve teeth (C) and matching teeth on the gear for wear (rounded off).





4. Inspect the gear hub thrust surface (A) for wear.
5. Inspect the cone surface (B) for wear and roughness.
6. Inspect the teeth on all gears (C) for uneven wear, scoring, galling, and cracks.
7. Coat the cone surface of the gear (B) with oil, and place the synchro ring on it. Rotate the synchro ring, making sure that it does not slip.








8. Measure the clearance between the synchro ring (A) and gear (B) all the way around. Hold the synchro ring against the gear evenly while measuring the clearance. If the clearance is less than the service limit, replace the synchro ring and synchro cone.
Synchro Ring-to-Gear Clearance Standard:
5th, 6th gear: 0.75 - 1.00 mm (0.030 - 0.039 inch)
Reverse gear: 0.85 - 1.10 mm (0.033 - 0.043 inch)
Service Limit: 0.4 mm (0.016 inch)
Double Cone Synchro-to-Gear Clearance
Standard:
(1): Outer Synchro Ring to Synchro Cone 1st, 2nd, gear: 0.70 - 1.09 mm (0.028 - 0.043 inch)
3rd, 4th gear: 0.90 - 1.39 mm (0.035 - 0.055 inch)
(2): Synchro Cone to Gear 1st, 3rd, 4th gear: 0.50 - 1.04 mm (0.020 - 0.041 inch)
2nd gear: 0.65 - 1.78 mm (0.026 - 0.070 inch)
(3): Outer Synchro Ring to Gear 1st, 3rd, 4th gear: 0.95 - 1.68 mm (0.037 - 0.066 inch)
2nd gear: 0.70 - 1.82 mm (0.028 - 0.072 inch)
Service Limit:
(1): 0.3 mm (0.012 inch)
(2): 0.3 mm (0.012 inch)
(3): 0.6 mm (0.024 inch)