TM 9-2320-289-20
1-16.
DRIVETRAIN SYSTEM.
a.
Functions to convert horsepower frorn engine into mechanical force needed to move
truck.
b. Major components of drivetrain are:
(1)
(2)
(3)
(4)
Engine:
(a)
6.2 liter diesel fueled V-8.
(b)
There is no carburetor on a diesel engine. Instead, fuel is injected under high
pressure through nozzles into the combustion chamber at correct timing
intervals.
(c)
ignition of fuel occours because of heat developed in combustion
prechamber. As a result, no spark plugs or high-voltage ignition system is
required. For cold starts, glow plugs heat up combustion prechamber,
(d) Vacuum pump driven by engine supplies shift signals to transmission.
Transmission:
(a)
GM Hydra-matic 400 automatic with neutral, reverse, and 3 forward gears.
(b) Provides operator with a selection of gear ranges while holding engine
speeds within effective torque range.
(c)
Includes a 3-element torque converter and a compound planetary gear set
with clutches and bands controlled by hydraulic system.
Transfer Case:
(a)
(b)
(c)
(d)
(e)
All trucks, except M1028A1 , M1028A2, and Ml 031, are equipped with a New
Process Model 238 transfer case.
M1028A1 , M1028A2, and M1031 are equipped with a New Process Model
205 transfer case, which is designed to accommodate installation of a power
take-off (PTO) unit (uses engine power to run auxiliary equipment).
Directs engine-to-transmission power to rear wheels for two-wheel drive or
to front and rear wheels for four-wheel drive.
Manually locking hubs must be set by hand to “LOCK” position before
shifting from two-wheel to four-wheel drive operation.
Bolted directly to an adapter plate behind transmission. No intermediate
propeller shaft needed.
Propeller Shafts:
(a)
Transmit driving force from transer case to front and rear axle differentials.
(b) Slip joints are installed to compensate for varying lengths of propeller shafts.
(c)
Universal joints compensate for changes in drive angle of propeller shafts.
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