Synchronizers Disassemble (M3L)

If you are servicing this transmission for a shifting concern such as clash, hop out of gear, or block-out in a particular gear, the following hardware must be replaced as a set for the gear in question. Adjoining gears do not need to be serviced unless necessary:

• Main gear in question - for example 2nd, 3rd
• Synchronizer assembly, slider sleeve assembly
• Blocker ring assembly
• Shift fork inserts, pads

1st/2nd, 3rd/4th, 5th/6th Synchronizers

IMPORTANT:

Synchronizer components are not interchangeable. Keep all the synchronizer components separate. The synchronizer hubs and the sliding sleeves are a selected assembly. Keep the hubs and the sliding sleeves together as originally assembled.

Fig 1: Scribe Mark On Synchronizer Hub And On Sleeve
Courtesy of GENERAL MOTORS COMPANY
1. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.
Fig 2: Synchronizer Sleeve, Synchronizer Inserts And Hub
Courtesy of GENERAL MOTORS COMPANY
2. Remove the synchronizer sleeve (2) and synchronizer inserts (1) from the hub (3).

Reverse Synchronizer

Fig 3: Scribe Mark On Synchronizer Hub And On Sleeve
Courtesy of GENERAL MOTORS COMPANY
1. Scribe a mark on the synchronizer hub and on the sleeve. This will help you to reinstall the parts in the same position.
Fig 4: Synchronizer Sleeve, Hub & Inserts
Courtesy of GENERAL MOTORS COMPANY
2. Remove the synchronizer sleeve (1) from the hub (2). Press against the inner hub.
3. Turn the hub over. The inserts (3) will slide out from the hub.