Important: When you service the synchronizers, retain them in the order that they
are removed. Mark the parts to ensure the correct position for inspection
and assembly.
- Clean all the synchronizer parts in a suitable cleaning solvent and
air dry all the parts.
- Inspect the 1st/2nd gear and the 3rd/4th gear synchronizer hubs
for a force fit on the output shaft.
- Replace synchronizer hubs that do not require a force fit.
- Inspect the synchronizer hub for wear on the external splines.
A stepped effect on the teeth, due to wear, may cause shift concerns.
- Replace a worn hub.
- Correct the cause, such as, but not limited to the following conditions:
| • | Engine related vibrations |
| • | Driving at a low speed in a high gear |
| • | Defective vibration damper or crankshaft |
- Inspect the synchronizer
sleeve teeth (a) for the following conditions, which may cause shift
concerns:
- Inspect the synchronizer sleeve detent stops (b) for wear
or for being chipped off.
- Replace the synchronizer assembly if the teeth or stops show the
above conditions.
- Inspect the synchronizer
blocker rings for worn away grooves (a).
- Replace the blocker ring assembly if the blocker ring grooves
are worn.
- Inspect the synchronizer
blocker rings for worn shift teeth.
- Inspect the internal ring for being warped or damaged.
- Inspect the outer ring for worn grooves.
- Replace the synchronizer assembly for any of the above conditions.
- Install the synchronizer blocking rings to the correct speed gear.
- Inspect the braking effect of the blocking ring. Turn the blocking
ring in one direction while pushing to the gear cone. Ensure the ring locks.
- If the ring does not lock, replace the synchronizer assembly.
- Except for 5th gear, measure
the blocker ring to gear clearance.
| 19.1. | Assemble the correct blocker ring to the correct gear. |
| 19.2. | Apply pressure to the blocker ring to fully seat the ring. |
| 19.3. | Using a feeler gage, measure between the blocker ring teeth and
the teeth on the gear. |
Specification
| • | Minimum Clearance 4th Gear: 0.8 mm (0.031 in) |
| • | Minimum Clearance 3rd Gear: 0.8 mm (0.031 in) |
| • | Minimum Clearance 2nd Gear: 0.8 mm (0.031 in) |
| • | Minimum Clearance 1st Gear: 0.8 mm (0.031 in) |
- If using a NEW blocker ring and the standard clearance can not
be obtained, replace the gear.
- Install the reverse synchronizer inner ring, internal ring, and outer
ring to the 5th synchronizer ring.
- Inspect the braking effect of the blocking ring. Turn the reverse
outer ring in one direction while pushing to the 5th synchronizer ring. Ensure
the ring locks.
- If the ring does not lock, replace the synchronizer assembly.
- Inspect the pressure pieces
for wear or damage.
- Inspect the springs for distortion.
- Replace the worn pressure pieces or faulty springs.
