Peterbilt Medium Duty Truck Owner's Manual - Peterbilt Motors

STARTING AND OPERATING THE VEHICLE
Transmission Warm–Up
In cold weather [below 32°F (0°C)], you may find shifting
sluggish when you first start up. Transmission warm-up is
especially important at this time, but it is always a good
idea to warm your transmission oil before starting out on
the road.
To warm the transmission lubricating oil during engine
warm-up:
1. Put the transmission in Neutral.
2. Release the clutch pedal and let the transmission
operate in Neutral for three to five minutes prior to
shifting into either a forward or reverse range.
Putting the Vehicle in Motion
After making sure the vehicle's oil and air pressure are
correct and all other parts and systems are in proper
working condition:
1. If your truck is equipped with a hand throttle, disengage
the hand throttle before driving the vehicle.
OPERATING THE TRANSMISSION
2. Fully depress the clutch pedal until the clutch brake
makes contact (see page 100). The contact will occur
at about 1 inch or less from the floorboard.
• The total stroke of the clutch pedal is about 10
inches. The first 1½ inches is free travel. After the
free travel comes the release stroke, which is the
part that fully releases the clutch. The last inch
engages the clutch brake.
• Always start out in a low gear. Starting in a higher
gear, even with a light load, will cause a very jumpy
start and excessive wear.
CAUTION: Always use first gear or a low
speed range to start the vehicle in motion.
The use of a higher gear or speed range
forces undue strain on the engine, clutch,
other transmission components, and may
cause damage.
3. Evaluate the road surface conditions and terrain your
vehicle is on. Select a gear low enough to let your
vehicle start forward with the throttle at idle.
4. Push the parking brake valve handle (Yellow) against
the dash panel to release the brakes.
Medium Duty (R05/09) Y53-6027 – 99 –