DRIVE EFFICIENTLY AND ECONOMICALLY

TM 9-2320-273-10

b. Driving in the City:

Engine rpm should be not less than 1,500 rpm for city

driving.

Operate the truck in a high gear at reduced engine rpm to maintain the lawful

speed. By reducing engine speed you are conserving fuel and lowering the noise

level of the vehicle. Also when slowing down for towns and other posted speed

zones along your highway route, remain in your running gear and reduce engine

rpm. Avoid downshifting until you are ready to return the truck to highway

speed. Recommended rpm range, depending on gear selection, must not be less

than 1,500 rpm for city driving.

c. Hauling Up Hill:

The engine works hardest when moving a loaded truck up a grade. The proper

use of gears will shorten time on hills and minimize the amount of shifting.

As you start uphill, depress the accelerator pedal all the way down and keep it

there as the truck moves up the grade. If there is enough power to maintain a

satisfactory rpm, remain in that gear for the entire grade.

If the hill causes a steady decline in engine rpm, downshift when engine rpm is at

or below 1650 rpm. Continue to downshift in this manner until engine rpm can

be maintained.

By remaining in each gear until arriving at the next lower shift point, your truck

will top the grade in the best possible time on less fuel and fewer shifts.

d. Using the Engine as a Braking Force:

Do not use engine retarder in first, second or third gears

except when descending steep grades. Never allow engine

speed to drop below 1200 rpm with the engine retarder

applied. Serious transmission damage will result. Do not

engage the engine retarder when shifting or when the

transmission is in neutral.

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