NEUTRAL
The input gear supplies input torque from the engine crankshaft via the clutch assembly. All gears turn, but the
synchronizers are not engaged with the gear teeth. Because the synchronizers are not engaged, power is not trans-
ferred to the main shaft.
1ST GEAR
The 1-2 synchronizer (2) sleeve shifts rearward to engage with the clutch teeth on the first speed gear (1). In this
condition, the power from the input gear is transmitted through the cluster gear to the first speed gear. Power is
transferred from the speed gear, across the synchronizer sleeve to the main shaft. The gear ratio for first gear is
2.66:1.
2ND GEAR
The 1-2 synchronizer (2) sleeve shifts forward to engage with the clutch teeth on the second speed gear (10). In
this condition, the power from the input gear will go through the cluster gear, across the second speed gear, and
into the synchronizer sleeve. The sleeve turns the synchronizer hub and main shaft. The gear ratio for second gear
is 1.78:1.
3RD GEAR
The 3-4 synchronizer (1) sleeve moves rearward to engage with the clutch teeth of the third speed gear (11). The
power is transferred through the input gear to the cluster gear, across the third speed gear, to the synchronizer
sleeve. The sleeve turns the synchronizer hub and the main shaft. The gear ratio for third gear is 1.30:1.
4TH GEAR
The 3-4 synchronizer (1) sleeve moves forward to engage with the clutch teeth of the fourth speed gear (12). Input
power is transferred straight through the input gear into the synchronizer sleeve. The sleeve turns the synchronizer
hub and the main shaft. The gear ratio for fourth gear is 1.00:1.
5TH GEAR
The 5-6 synchronizer (3) sleeve moves rearward to engage with the clutch teeth of the fifth speed gear (7). In this
condition, the power from the input gear is transferred through the cluster gear to the cluster gear extension. Power
then flows from the extension into the synchronizer hub. The hub turns the synchronizer sleeve, fifth speed gear
and the main shaft. The gear ratio for fifth gear is 0.74:1.
6TH GEAR
The 5-6 synchronizer (3) sleeve moves forward to engage with the clutch teeth of the sixth speed gear (8). In this
condition, the power from the input gear is transferred through the cluster gear to the cluster gear extension. Power
then flows from the extension into the synchronizer hub. The hub turns the synchronizer sleeve, sixth speed gear
and the main shaft. The gear ratio for sixth gear is 0.50:1.
REVERSE
The reverse gear synchronizer (4) moves rearward to engage with the reverse speed gear (6). Input power from the
input gear travels through the cluster gear to the cluster gear extension. Power flows from the reverse cluster gear
to the reverse idler gear, and across the reverse speed gear and synchronizer sleeve to the main shaft. The input
gear moves in a clockwise direction, turning the cluster gear and its extension in a counter-clockwise direction. The
cluster gear and extension turn the reverse idler gear (5) in a clockwise direction, and the idler gear turns the
reverse speed gear in a counter-clockwise direction, resulting in reverse. The gear ratio for reverse gear is 2.90:1.
DIAGNOSIS AND TESTING
MANUAL TRANSMISSION - T56
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the result of a leak, inadequate lubricant fill or incorrect lubricant level
check.
21 - 236
MANUAL TRANSMISSION - T56 - SERVICE INFORMATION
DR/DH