TM-9-2320-344-10

TRUCK, CARGO, GUIDED MISSILE TRANSPORTER (GMT), 8X8, M985A4GMT

TECHNICAL MANUAL; OPERATOR'S MANUAL

OCTOBER 2008
TM-9-2320-344-10

  TM-9-2320-344-10 - Page 113 of 1012

NOTE
•
The air system includes the necessary valves and air lines to control
the vehicle's air-operated parts.
•
On the M983A4 LET tractor vehicle, air from reservoir is controlled
by the winch tensioner and winch declutch manual valves, which in
turn operate the heavy-duty winch kickout and cable hold down
systems.
Pressurized air from the air compressor (6) is passed through the air dryer (7) to the
reservoir (1) - also called the “wet tank.” The air dryer (7) removes dirt and moisture from
the pressurized air.
Once air pressure in reservoir (1) rises above 65 to 75 psi (4.5 to 5.2 bar), a valve opens
and allows reservoirs (2, 3, 4, and 5) to be pressurized up to 133 psi (9.2 bar).
Air from reservoir (4 and 5) goes to the brake treadle valve (8). This air controls the rear
axle service parking brakes (9). Air pressure for reservoirs (4 and 5) is displayed by REAR
air pressure gauge (10).
Air from reservoir (2 and 3) goes to the brake treadle valve (8). This air controls the front
axle service brakes (11). Air pressure for reservoirs (2 and 3) is displayed by FRONT air
pressure gauge (12).
The PARKING BRAKE valve (13) controls air from reservoirs (4 and 5) and applies or
releases the rear axle service parking brakes (9).
Reservoirs (2 and 3 or 4 and 5) are interconnected so that if one reservoir fails, air is supplied
to release the rear axle service parking brakes (9) from whichever reservoir is functioning.
A buzzer will sound and the brake system failure (low air) indicator (14) will illuminate if air
pressure falls below 65 to 75 psi (4.5 to 5.2 bars).
NOTE
•
There is a SPNSN LOW AIR indicator that warns when the
suspension system is low with air and it will not dump.
•
A SPNSN LOW AIR indicator will illuminate if one or more zones of
air springs are deflated.
Specific to the M984A4, the front brake actuator valve (15) is used to apply the front axle
service brakes when using heavy-duty winch.
END OF WORK PACKAGE
TM 9-2320-344-10
0008
0008-3
/(0008-4 blank)


Back to Top