Chapter 10 Manual Transaxle Construction and Operation 211
Copyright by Goodheart-Willcox Co., Inc.
Needle bearing
Ball bearing
Synchronizer ring
Synchronizer spring
Reverse gear
synchronizer sleeve
Synchronizer hub
5th gear
Assembled
output shaft
Synchronizer
spring
Synchronizer
ring
1st gear
Needle bearing
Thrust washer
4th gear
3rd gear
2nd gear
Spacer collar c
Locknut
Spring washer
Spacer collar
31 × 38 × 30.5 mm
Output shaft
Output Shaft Assembly
Input shaft
Oil passages
Output shaft
Oil passage
Outer sleeve
Teeth in outer
sleeve for
reverse gear
Insert springs (2)
Inserts (3)
Inner hub
A
B
Figure 10-10. Synchronizers (shown here) act as clutches,
bringing mating gears to the same speed before they are fully
engaged. Blocking rings, considered part of the synchronizer
assembly, are not shown here. A—The synchronizer is similar to
that found in rear-wheel drive manual transmission. B—The
gear cut into the outer sleeve of this synchronizer serves as
reverse gear. (Chrysler)
Figure 10-9. In these input and output shafts, oil passages are
used for lubricating bearings. (Honda)
Figure 10-8. Exploded view of a transaxle output shaft. (Honda)
Synchronizers
Before freewheeling gears can be locked to the turning
shaft on which they ride, they must be turning at almost the
same speed as the shaft. This is done in the transaxle trans-
mission with gear synchronizers, Figure 10-10. The syn-
chronizers are placed along the shaft between these gears,
and they are splined to the shaft. They match the speed of
mating gears to their own speed (output shaft speed) in the
process of locking a gear to its shaft. If the gear speeds were
not synchronized in this way, the gears would grind against
each other before meshing, causing gear clash. As a result,
shifting would be difficult and noisy, and the gears could be
damaged.
Manual transaxle transmissions are synchronized in
all forward gears. Reverse gear is unsynchronized.