Descending A Grade; Engine Overspeed - Peterbilt 348 2017 Operator's Manual

Descending a Grade

WARNING!
Do not hold the brake pedal down
too long or too often while going
down a steep or long grade. This
could cause the brakes to overheat
and reduce their effectiveness. As a
result, the vehicle will not slow down
at the usual rate. To reduce the risk
of an accident which could cause
death or personal injury, before go-
ing down a steep or long grade, re-
duce speed and shift the transmis-
sion into a lower gear to help control
your vehicle speed. Failure to follow
procedures for proper downhill oper-
ation could result in loss of vehicle
control.
(03/17)

Engine Overspeed

CAUTION
To avoid engine damage, do not let
the engine rpm go beyond the maxi-
mum governed rpm—valve damage
could result if overspeed conditions
occur.
NOTE
Often these recommendations are
secondary to maintaining an ade-
quate and safe speed relative to the
surrounding traffic and road condi-
tions.
Operate the engine within the optimum
engine rpm range and do not allow
the rpm's to exceed the maximum
governed speed. See your Engine
Operation and Maintenance manual
for information regarding engine rpm.
When the engine is used as a brake
to control vehicle speed (e.g., while
driving down a grade), do not allow
Y53-6060-1C1
DRIVING TIPS AND TECHNIQUES
the engine rpm to exceed maximum
governed speed.
Under normal load and road conditions
operate the engine in the lower end of
the range.
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