TM 9-2320-269-10
REVIEWING DRIVING GUIDELINES
After prolonged engine operation, or using the PTO, idle the engine from three to five minutes before shutting the engine
down. This few minutes of idling allows the lubricating oil and coolant to carry heat away from the iron masses of the
engine block.
The most practical engine rpm cruising speeds for highway operation Is one that permits legal road speeds and fuel
economy. The suggested cruising range for the M876 truck, on highway, Is 1,800 - 1,900 rpm.
In the city and other reduced speed zones, match engine speed to the lower road requirements to conserve fuel and lower
vehicle noise level. Select a drive gear range of not less than 1,500 rpm.
When downshifting for power on grades, wait for the transmission automatic shift points before making the down shift. If
you can maintain a satisfactory engine speed on grades in the 2-5 drive range it is not necessary to down shift at all. See
Avoid overspeeding the engine beyond the 3,000 rpm, maximum governed speed, when rolling downgrade.
Never operate the engine at high rpm while in a low drive gear, when restricted by 20-25 mph (32-40 km/h) speed limits.
This wastes fuel and creates unnecessary vehicle noise.
Avoid unnecessary prolonged engine Idling. During long engine idling periods, the engine coolant temperatures will fall
below NORMAL operating range. The incomplete combustion in a cold engine will cause crankcase dilution, formation of
gummy deposits on valves, pistons, and rings and rapid accumulation of sludge In the engine.
Frequently check gages and indicators during normal driving operations. See pages 2-68 and 2-69.
Avoid oversteering. Become familiar with the steering characteristics of the M876 truck before attempting maneuvers in
limited spaces.
DRIVE CAREFULLY! AT ALL TIMES!
2-89