TM 9-2320-260-20
Special purpose bodies systems include those controls, hydraulics, and other related components which
will enable a vehicle to perform a specific task outside basic vehicle operation. Major parts will be described
for each of the following systems:
a. Medium Wrecker Crane and Rear Winch Controls Operation (M816) (page 1-64.
b. Dump Body Hydraulic System Operation (M817) (page 1-66).
c. Auxiliary Trailer Power Systems Operation (M818) (page 1-68).
d. Troop Seats and Side Racks Operation (M813, M813A1, M814) (page 1-69).
e. Tractor Wrecker Crane Hydraulic System Operation (M819) (page 1-70).
f. Expansible Van Liftgate Hydraulic System Operation (M820A2) (page 1-72).
a. Medium Wrecker Crane and Rear Winch Controls Operation (MM816).
The M816 medium wrecker truck is used for wrecker and salvage operations. It is equipped with a
hydraulically-operated crane that can extend to a length of 18 ft (5.49 m), elevates 45 degrees, swings 270
degrees, and is capable of lifting loads up to 20,000 lbs (9,072 kg). The wrecker crane and winch control
system converts power from the engine into hydraulic and mechanical power. This allows the operator to
perform crane and rear winch operations outside of the vehicle. Major components are:
A REAR WINCH SHIFT LEVER - Controls turning of rear winch drum.
B CRANE DRIVE CONTROL LEVER - Pulled back to engage power for crane operation.
C
THROTTLE CONTROL LEVER - Used to control engine speed during winching operations.
D ENGINE CLUTCH CONTROL LEVER - Used to engage and disengage engine clutch for rear
winch or crane operations.
E
CABLE TENSIONER CONTROL VALVE LEVER - Used to apply tension to slack cable when
rewinding.
F
REAR WINCH CONTROL ROD - Connects rear winch shift lever with power divider linkage.
G AIR CHAMBER - Provides mechanical power to rear winch cable tensioner.
H CRANE DRIVE CONTROL ROD - Connects power divider to hydraulic pump to power crane.
THROTTLE CONTROL CABLE - Connects throttle control lever (C) with engine fuel pump
I
governor for controlling engine speed during winching.
1-64
