1-9. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS. - Continued
Transmission and Drive Train.
The truck is equipped with an automatic transmission that provides five-forward and one-reverse gear. .
The transmission is connected to the engine via a torque converter that functions both as a fluid coupling and a torque
multiplier. A torque converter lock-up clutch provides direct drive between engine and transmission when the vehicle
obtains sufficient speed. This lock-up automatically disengages when the speed drops to the downshift limit of the gear
range in which the vehicle is traveling. The transmission contains four sets of planetary gears and six hydraulically
activated clutch packs. Engagement of the clutches and gears is controlled by means of the gear selector control in the
cab and an automatic, governor-controlled shift mechanism in the transmission.
The drive train from the transmission to the wheels consists of two drive shafts, and the rear and front
axles, (see fig. 1-11). The rear axle is provided with a power divider gearing and clutch, controlled by the driver, for
selection of either 2or 4-wheel drive.
The drive shaft between the front and rear axle is a two-part unit supported by a center bearing. The front
and rear axles are both equipped with single reduction, controlled traction (differential lock) differentials to ensure
positive traction on all four wheels. The controlled traction mechanism is engaged and disengaged from the cab. The
front axle is provided with ball and socket mounted wheel ends.
The wheels consist of four single-unit rims mounted with tubeless, bias-ply tires suitable for both on and
Figure 1-11. Transmission and Drive Train Components