Cooling System Tips — Automatic Transmission
To reduce the potential for engine and transmission
overheating in high ambient temperature conditions,
take the following actions:
•City Driving — When stopped, shift the transmission
into NEUTRAL and increase engine idle speed.
•Highway Driving — Reduce your speed.
•Up Steep Hills — Select a lower transmission gear.
•Air Conditioning — Turn it off temporarily.
NOTE:If the coolant temperature is too high the A/C
will automatically turn off.
Do Not Operate The Engine With Low Oil
Pressure
If the low oil pressure warning light turns on while driving,
stop the vehicle and shut down the engine as soon as
possible. A chime will sound when the light turns on.
NOTE:Do not operate the vehicle until the cause is
corrected. This light does not show how much oil is in the
engine. The engine oil level must be checked under the
hood.
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
4
STARTING AND OPERATING 67
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting And Operating” for
further information.NOTE:The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of
the air suspension system.
DIESEL EXHAUST FLUID
Your vehicle is equipped with a Selective Catalytic Reduction
system to meet the very stringent diesel emissions standards
required by the Environmental Protection Agency.
The purpose of the SCR system is to reduce levels of NOx
(oxides of nitrogen emitted from engines) that are harm-
ful to our health and the environment to a near-zero level.
Small quantities of Diesel Exhaust Fluid (DEF) is injected
into the exhaust upstream of a catalyst where, when
vaporized, it converts smog-forming nitrogen oxides
(NOx) into harmless nitrogen (N2) and water vapor
(H2O), two natural components of the air we breathe.
You can operate with the comfort that your vehicle is
contributing to a cleaner, healthier world environment
for this and generations to come.
90 STARTING AND OPERATING
MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides those maintenance items specified in the fixed
maintenance schedule, there are other components which
may require servicing or replacement in the future.
CAUTION!
•Failure to properly maintain your vehicle or per-
form repairs and service when necessary could
result in more costly repairs, damage to other
components or negatively impact vehicle perfor-
mance. Immediately have potential malfunctions
examined by an authorized dealership or qualified
repair center.
(Continued)
CAUTION!(Continued)
•Your vehicle has been built with improved fluids
that protect the performance and durability of your
vehicle and also allow extended maintenance inter-
vals. Do not use chemical flushes in these compo-
nents as the chemicals can damage your engine,
transmission, power steering or air conditioning.
Such damage is not covered by the New Vehicle
Limited Warranty. If a flush is needed because of
component malfunction, use only the specified
fluid for the flushing procedure.
5
MAINTAINING YOUR VEHICLE 101
•Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
•Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory engine coolant (antifreeze)
performance, poor gas mileage, and increased emis-
sions.
Charge Air Cooler — Inter-Cooler
The charge air cooler is positioned in front of the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and throughanother hose to the intake manifold of the engine. This
cooling process enables more efficient burning of fuel
resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
Brake System
Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the “Brake System Warning Light” indicates
system failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
118 MAINTAINING YOUR VEHICLE
Cooling System Tips — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•City Driving —
When stopped, shift the transmission into NEUTRAL
and increase engine idle speed.
•Highway Driving —
Reduce your speed.
•Up Steep Hills —
Select a lower transmission gear.
•Air Conditioning —
Turn it off temporarily.
Do Not Operate The Engine With Low Oil Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:
•engine misfiring or vibrating severely
4
STARTING AND OPERATING 221
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Electronic Speed Control — If Equipped
•Do not use in hilly terrain or with heavy loads.
•When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
•Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
278 STARTING AND OPERATING
MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides those maintenance items specified in the fixed
maintenance schedule, there are other components which
may require servicing or replacement in the future.
CAUTION!
•Failure to properly maintain your vehicle or per-
form repairs and service when necessary could
result in more costly repairs, damage to other
components or negatively impact vehicle perfor-
mance. Immediately have potential malfunctions
examined by an authorized dealership or qualified
repair center.
(Continued)
CAUTION!(Continued)
•Your vehicle has been built with improved fluids
that protect the performance and durability of your
vehicle and also allow extended maintenance inter-
vals. Do not use chemical flushes in these compo-
nents as the chemicals can damage your engine,
transmission, power steering or air conditioning.
Such damage is not covered by the New Vehicle
Limited Warranty. If a flush is needed because of
component malfunction, use only the specified
fluid for the flushing procedure.
6
MAINTAINING YOUR VEHICLE 291
•If frequent engine coolant (antifreeze) additions are
required, the cooling system should be pressure tested
for leaks.
•Maintain engine coolant (antifreeze) concentration at a
minimum of 50% OAT coolant (conforming to MS-
12106) and distilled water for proper corrosion protec-
tion of your engine which contains aluminum compo-
nents.
•Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
•
Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install ONLY
the correct type thermostat. Other designs may result in
unsatisfactory engine coolant (antifreeze) performance,
poor gas mileage, and increased emissions.
Charge Air Cooler — Inter-Cooler
The charge air cooler is positioned below the radiator and
the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50° to 100°F
(10° to 38°C). This cooling process enables more efficient
burning of fuel resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
6
MAINTAINING YOUR VEHICLE 315