Peterbilt 325 2017, Operator'S Manual

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DRIVING TIPS AND TECHNIQUES
Use of Tachometer
The tachometer is an instrument that
aids in obtaining the best performance
of the engine and manual transmission,
serving as a guide for shifting gears.
Refer to the Engine Operation and
Maintenance manual for optimum
engine rpm.
•
If the engine rpm moves beyond
the maximum governed speed,
indicating an overspeed condition,
apply the service brake or shift to
a higher gear to bring engine rpm
within the optimum speed range.
•
When driving downhill: shift to a
lower gear, use the engine brake
(if so equipped), and use the
service brake, keeping the engine
speed below 2,100 rpm.
When the engine speed reaches
its maximum governed speed, the
injection pump governor cuts off fuel
to the engine. However, the governor
has no control over the engine rpm
when it is being driven by the vehicle's
transmission, for example, on steep
downgrades. Apply service brakes or
shift to a higher gear.
Fuel economy and engine performance
are also directly related to driving
habits:
•
The best results in trip time and
fuel economy are obtained while
driving the vehicle at a steady
speed.
•
Shift into higher or lower gears (or
apply the service brake) to keep
engine rpm near the lower end of
the optimum operating range.
•
Avoid rapid acceleration and
braking.
Fuel - Excess Consumption
The vehicle's fuel consumption is
connected to three important factors:
maintenance, driving habits, and
general condition of the road, traffic
conditions, and vehicle load.
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Y53-6060-1C1 (03/17)
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