MM3670, Lesson 1
clamped securely to the muffler. Check the muffler to make sure it is in good condition and
mounted securely to the vehicle. Check the tail pipe to make sure it is securely clamped to
the muffler. The tail pipe must be properly supported and unobstructed at its outer end, and
must extend beyond the saddle tanks of the tractor. Check the entire exhaust system to
make sure that there are no exhaust leaks at any connection. An exhaust leak could be a
Item 11. Check the type of fuel used. It must be either gasoline or diesel. The Army prohibits liquid
petroleum gas (LPG) fuel for vehicles carrying ammunition. (Other services may allow its
use.) Vehicles that burn LPG can be identified quickly by the pressure-regulating valves in
the fuel line near the tank and the breather pipe extending from the tank to the top of the
Item 12. Check fuel tanks and fuel lines to make sure they are mounted securely and that there is no
evidence of leakage.
Item 13. This item concerns the fifth wheel rocker plate and bed (if you are inspecting a tractor and
trailer) and the kingpin locking lever. Check the fifth wheel rocker plate and bed to make
sure they are properly assembled, mounted, and lubricated. Inspect the kingpin locking
lever to make sure it is free-moving and that it locks securely. Look for signs of wear and
Item 14. Inspect the brakes as follows: Have the driver turn on the engine, set the hand brake, and
try to drive the vehicle. The vehicle should not move. Have the driver turn the engine off.
Next, inspect the complete air system, if the vehicle has one. Turn the ignition switch to On,
but don't start the engine. Open the petcock on the air tank and hold your hand in the
escaping air. If excessive moisture forms on your hand, the tank or tanks have water in
them. With the petcock still open, look at the air pressure gauge inside the cab. The gauge
pressure reading should be decreasing, which indicates that the gauge is working properly.
When the decreasing air pressure reaches the danger point, a warning buzzer should
sound. When it sounds, turn off the ignition switch and close the air tank petcocks. Have
the driver start the engine and refill the air tanks, letting them fill until the governor cuts off.
Have the driver move the vehicle a short distance and try the brakes to see if the brake
pedal has excessive travel.
Item 15. Check the landing gear assembly to make sure it is in working order.
Item 16. When inspecting springs and associated parts, check behind the wheels for oil or grease
leaks around the drum flanges, and inspect the air lines for leaks. Inspect the springs,