freightliner 108SD, Driver Manual

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NOTICE
Do not allow the engine to exceed its governed
speed, or serious engine damage could result.
NOTE: The exhaust brake is only active when
engine speed is between 1100 and 2700 rpm.
4.
While going down the grade, use a low enough
gear to safely descend with a minimum applica-
tion of the service brakes. As a general guide-
line, use the same gear as you would to ascend
the hill.
The following conditions should exist if the brake
is operating properly:
•
A slight change in the sound of the engine
may be noticed when the exhaust brake is
applied.
•
Exhaust smoke should appear normal.
•
Engine temperature should remain in the
normal operating range.
•
Road speed usually decreases when the
exhaust brake is applied during a descent.
When the vehicle is carrying a heavy load
or the grade is extremely steep, you may
need to apply the service brakes occasion-
ally.
•
Do not expect a retarding effect similar to
sudden hard application of the service
brakes. The exhaust brake retards the ve-
hicle with a smooth braking effect.
•
During a descent, the tachometer usually
shows a drop in rpm, depending on the
grade and the vehicle load.
•
Depending on the grade and vehicle load,
you may or may not feel the retarding force
acting against your body when the brake is
applied. The retarding force of the brake
may not always be noticed, but it is actu-
ally preventing the vehicle from going
much faster.
5. Apply the service brakes to reduce the engine
rpm or make a slower descent by using a lower
gear.
6.
Make sure the exhaust brake is turned off before
shutting down the engine.
Power Takeoff (PTO) Governor
Engine power takeoffs (PTO) are devices used to tap
into engine power to run auxiliary devices, such as
hydraulic pumps that power additional equipment.
The following instructions are general guidelines for
operating a PTO.
1. Set the parking brake and put the transmission in
neutral.
2. Press the dash-mounted PTO switch. Release
the switch when the amber light behind the
switch begins to blink.
When the light is steadily illuminated, the PTO is
engaged and ready to operate. In stationary
mode, the vehicle must remain in neutral with the
parking brake set.
3. To activate the mobile mode, shift from neutral to
reverse, 1st, or 2nd gear. The clutch will open
and the PTO will disengage for a moment.
4. Touch the throttle pedal to close the clutch and
engage the PTO in mobile mode. The PTO may
be operated with the transmission in reverse,
neutral, 1st, or 2nd gears only.
NOTE: Do not attempt to change gears while
the vehicle is moving. The transmission will ig-
nore the request.
5. To end the mobile mode, bring the vehicle to a
stop. The clutch will open and shut down power
to the PTO.
6. To resume stationary mode, shift to neutral. The
PTO will engage.
7. To end stationary mode, press the dash switch.
When the light in the switch goes out, power to
the PTO is shut off.
Optional Engine Systems
10.6