TM 5-3805-261-20
PRINCIPLES OF OPERATION. (cont)
1-13.
130G GRADER. (cont)
h.
Front Axle Assembly. A trunnion mounted solid front axle swings a maximum of 32 degrees and provides
24 inches of ground clearance.
i.
Rear Axle Differential and Lock Differential. A four-wheeled tandem rear axle arrangement houses axle
shafts driven by a lock-unlock equipped differential. The axle shafts turn the final drive sprocket chains through planetary
reduction gears. The sprocket chains then drive the sprocket spindles and wheels.
j.
Air Brake System. The rear four-wheel brakes are air actuated and of multiple oil disc design. They are
housed within the wheel spindle housings. A pedal operated valve at the cab controls the braking air pressure. An engine
driven, two cylinder air compressor supplies a two section air reservoir to provide braking pressure.
The manually actuated multiple oil disc parking/emergency brake located in the transmission case is spring engaged and
air disengaged. A dual circuit air system arrangement maintains one half of the service braking power in the event of a
brake system circuit malfunction. If service brakes are lost, the parking/emergency brake can be applied.
k.
Wheels and Tires. Rim and wheel assemblies are interchangeable. There are six tubeless 13-24 (8 PR)
traction type tires.
l.
Steering. The engine driven main hydraulic system pump powers two hydraulic steering cylinders, controlling
the front wheels. An electrical supplemental steering pump is automatically actuated and supplies power for steering in
the event that the main pump fails. The articulated cylinders are driven by the main hydraulic pump.
m.
Frame, Towing Attachments, Drawbars and Articulation System. A frame and case at the rear section of
the vehicle serves as a mounting for the engine, rear wheels and drive train. A front frame section serves as a mounting
for the cab, earthmoving components and front wheels. The two sections are articulated (hinged) at the center of the
vehicle. The angle of articulation is controlled by hydraulic cylinders driven by the main hydraulic pump. There is a tow pin
at each end of the vehicle.
n.
Cab and Hood. A low profile ROPS (Rollover Protective Structure) and FOPS (Falling Object Protective
Structure) cab protects operator from dust, sound and weather. It also houses the controls and instrumentation. An
engine and radiator hood with side door assemblies provides sound suppression and weather protection.
o.
Bumper. One bumper equipped with a tow pin is located at the rear of the vehicle.
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