If these modified engine performance
characteristics persist for an extended
period and either the service engine soon
or powertrain malfunction, reduced power,
electronic throttle control light is
illuminated, have the system checked by
an authorized dealer.
Service engine soon
Powertrain malfunction, reduced
power, electronic throttle control
Diesel Lubrication System
It is important to change the engine oil at
the recommended service intervals or
when indicated by the information display
to maintain oil viscosity. Extending the oil
and filter change interval beyond the
recommended interval can negatively
affect engine performance, fuel economy
and engine life. See Engine Oil Check
(page 224).
Engine and secondary cooling system
The cooling system contains a primary
cooling loop to cool the engine and a
secondary cooling loop to cool the
transmission, charge air, and fuel. The
coolant serves three primary purposes: to
provide heat transfer, freeze point
protection, and corrosion protection using
additives.
Vehicles with diesel engines typically are
used to carry heavy loads and accumulate
mileage rapidly. These two factors may
cause the additives in the coolant to wear
out in a shorter time. You can find more
information about coolant additives and
coolant change intervals in the coolant
chapter. See General Maintenance
Information (page 319). Operating the
engine with insufficient coolant or coolant
additive can cause severe engine damage.Selective catalytic reduction system
Your vehicle is equipped with a selective
catalytic reduction system designed to
reduce emission levels of nitrogen oxides
from the exhaust of your diesel engine. This
system relies on the use of Diesel Exhaust
Fluid (DEF) that you must replenish at
certain intervals. Failure to maintain proper
DEF levels or if the DEF becomes
contaminated will result in vehicle speed
limitations or result in your vehicle entering
an idle-only mode. See Selective
Catalytic Reductant System (page 118).
Minor Troubleshooting Guide
If the engine won’t crank
WARNING: Battery posts,
terminals and related accessories
contain lead and lead compounds. Wash
hands after handling.
Turn on the headlights. If the lights are dim,
do not go on at all or when the ignition is
turned to the start position, the lights
become dim or go out, the battery
connections may be loose or corroded, or
the battery may be discharged. If there is
a clicking or stuttering sound coming from
the engine compartment when you turn
the key to the start position, this may also
indicate a loose or corroded battery
connection.
Check the battery connections at the
battery posts, cable connection to the
engine grounding point and at the starter
connection.
If you suspect a discharged battery, have
it checked and corrected.
9
Introduction
Engine starting (with parking brake applied)
Check the gauge (diesel engine) or indicator light (gasoline
engine) to verify the alternator is charging. Voltmeter
Inspect for excessive free play in the steering linkages. The
steering wheel should have less than 2 in (5 cm) of free play
at its rim. Steering linkage free play
Verify the parking brake holds the vehicle by gently trying to
pull forward with the parking brake applied. Parking brake
Verify operation using the following procedure. Chock the
wheels, if necessary. Push in the parking brake and, on
tractors, push in the tractor parking brake knob: Air brakes
1. Verify the air compressor or governor cutout pressure is
approximately 120 psi (827 kPa).
2. Turn off the engine, and then turn the key back to the on
position (without starting the engine).
3. Without the brake pedal applied, note the air pressure drop
for one minute. It should be less than 2 psi (14 kPa) for single
vehicles and 3 psi (21 kPa) for combination vehicles.
4. Press and hold the brake pedal with 90 psi (621 kPa) or
more. Make sure there is no more than a 3 psi (21 kPa) per
minute leak for single vehicles and a 4 psi (28 kPa) minute
leak for combination vehicles.
5. Pump the brake pedal to deplete the system of air pressure.
The warning light and tone should turn on at 57 psi (393 kPa).
6. Pump the brake pedal and make sure the parking brake
and trailer parking brake knobs pop out at 20 psi (138 kPa)
or higher.
Verify that the fluid level is in the proper operating range. See
Automatic Transmission Fluid Check (page 242). Automatic transmission
fluid
Front of vehicle
Verify all exterior lights illuminate and are clean. Lights
Check headlights function on high and low beam.
Verify reflectors are clean, unbroken and of proper color (red
on rear, amber elsewhere).
212
Vehicle Inspection Guide
