Abstract: A synchronizer (10) with improved blockers (41) and pre-energizers (43). The synchronizer includes blocker pins (40) that extend axially through blocker openings (41a) in a radially extending shift flange (32) and split pin pre-energizers (42) having pairs of members (44) extending axially through pre-energizer openings (43a) in the flange. The openings (41a,43a) are defined by blocker and pre-energizer rings (41,43) respective disposed in openings (32a,32b) in the flange.

Abstract: A pin-type, double-acting synchronizer mechanism (10) with friction rings (26, 46 and 28, 48), jaw members (30, 38 and 32, 40) axially secured together by retainers (44), three circumferentially spaced pins (50) including blocker shoulders for preventing asynchronous engagement of the jaw clutches, and pre-energizer assemblies (52) to ensure initial engagement of the friction rings and blocker shoulders in response to initial engaging movement of a shift flange (42), and self-energizing ramps (20a-20d and 62a-62d). The synchronizer includes improved jaw members and self energizing ramps, an improved shift flange, improved pre-energizers, and improved jaw member retainers.