ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If an
overheat warning appears on the instrument panel
cluster and/or DIC, stop the vehicle as soon as
possible. See Engine Overheating
on page 6‑34for
more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down. See Engine Coolant
Temperature Gage on page 4‑41.
See Overheated Engine Protection Operating Mode
on
page 6‑36for information on driving to a safe place in
an emergency.
ENGINE OVERHEATED STOP ENGINE
Notice: If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If an
overheat warning appears on the instrument panel
cluster and/or DIC, stop the vehicle as soon as
possible. See Engine Overheating
on page 6‑34for
more information.
This message displays and a chime may sound if the
engine cooling system reaches unsafe temperatures for
operation. Stop and turn off the vehicle as soon as it is
safe to do so to avoid severe damage. This message
clears when the engine has cooled to a safe operating
temperature.
ENGINE POWER IS REDUCED
This message displays and a chime may sound when
the cooling system temperature gets too hot and the
engine further enters the engine coolant protection
mode. See Engine Overheating
on page 6‑34for
further information.
This message also displays when the vehicle's engine
power is reduced. Reduced engine power can affect the
vehicle's ability to accelerate. If this message is on, but
there is no reduction in performance, proceed to your
destination. The performance may be reduced the
next time the vehicle is driven. The vehicle may be
driven at a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime this
message stays on, the vehicle should be taken to your
dealer/retailer for service as soon as possible.
FAST IDLE ON
If your vehicle has this feature, this message displays
when the fast idle feature is on. See Fast Idle System
on page 3‑25for more information.
FUEL LEVEL LOW
This message displays and a chime may sound if the
fuel level is low. Refuel as soon as possible. See Fuel
Gage
on page 4‑49and Fuelon page 6‑6for more
information.
4-67
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn out, the arrows on the
instrument panel will still flash for turns. It is important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gear beforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might get hot and no
longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. See Tow/Haul Mode on page 3‑34. When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If the engine
is turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar
to engine overheating. To avoid this, let the engine run
while parked, preferably on level ground, with the
automatic transmission in P (Park) for a few minutes
before turning the engine off. If the overheat warning
comes on, see
Engine Overheating on page 6‑34.
Parking on Hills
{WARNING:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on
a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into the curb if facing downhill
or into traffic if facing uphill.
5-72
A.Engine Air Cleaner/Filter on page 6‑21.
B. Coolant Surge Tank and Pressure Cap. See Cooling System on page 6‑30.
C. Positive (+) Terminal. See Jump Starting
on
page 6‑44.
D. Battery on page 6‑43.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
under Engine Oil on page 6‑18.
F. Automatic Transmission Dipstick. See “Checking
the Fluid Level” underAutomatic Transmission
Fluid (4-Speed Transmission)
on page 6‑23or
Automatic Transmission Fluid (6-Speed
Transmission) on page 6‑26.
G. Remote Negative (−) Terminal (Out of View). See Jump Starting on page 6‑44. H. Engine Oil Dipstick (Out of View). See
“Checking
Engine Oil” underEngine Oil on page 6‑18.
I. Engine Cooling Fan. See Cooling System
on
page 6‑30.
J. Power Steering Fluid Reservoir. See Power
Steering Fluid on page 6‑37.
K. Brake Master Cylinder Reservoir. See “Brake
Fluid” under Brakes on page 6‑39.
L. Underhood Fuse Block on page 6‑122.
M. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on
page 6‑38.
6-17
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑12for more information.
Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger side of the vehicle. See
Engine Compartment Overview
on page 6‑16for more
information on location.
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant surge
tank. If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down. If coolant is visible but the coolant level is not at or
above the FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant surge tank, but be sure the cooling system is
cool before this is done.
The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak in the
cooling system.
If the vehicle has a low coolant sensor and the LOW
COOLANT LEVEL message comes on and stays on, it
means you are low on engine coolant. See “LOW
COOLANT LEVEL” underDIC Warnings and Messages
on page 4‑65.
6-32
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait for that
to stop. A hiss means there is still some
pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixtureto the FULL COLD mark.
4. With the coolant surge tank pressure cap off, start the engine and let it run until the engine coolant
temperature gage indicates approximately
195°F (90°C). By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge
tank until the level reaches the FULL COLD mark.
5. Replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the coolant is cold. If necessary, repeat coolant fill
procedure Steps 1 through 6.
Notice: If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
If the vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
The vehicle has several indicators to warn of engine
overheating.
You will find a coolant temperature gage on the
vehicle's instrument panel. See Engine Coolant
Temperature Gage on page 4‑41.
In addition, you will find ENGINE OVERHEATED STOP
ENGINE, ENGINE OVERHEATED IDLE ENGINE, and
ENGINE POWER IS REDUCED messages in the Driver
Information Center (DIC) on the instrument panel.
See DIC Warnings and Messages on page 4‑65.
6-34
You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 8‑7.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run the
engine and have the vehicle serviced.
Notice: Engine damage from running your engine
without coolant is not covered by your warranty.
See Overheated Engine Protection Operating Mode
on page 6‑36for information on driving to a safe
place in an emergency.
Notice: If the engine catches fire while driving
with no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by the
vehicle warranty. See Overheated Engine Protection
Operating Mode
on page 6‑36for information on
driving to a safe place in an emergency.
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no
sign of steam or coolant before you open
the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
See Overheated Engine Protection Operating
Mode
on page 6‑36for information on driving to
a safe place in an emergency.
6-35
Notice:
.When using concentrated washer fluid,
follow the manufacturer's instructions for
adding water.
.Do not mix water with ready-to-use washer
fluid. Water can cause the solution to freeze
and damage the washer fluid tank and other
parts of the washer system. Also, water does
not clean as well as washer fluid.
.Fill the washer fluid tank only three-quarters
full when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
.Do not use engine coolant (antifreeze) in the
windshield washer. It can damage the
vehicle's windshield washer system and
paint.
Brakes
Brake Fluid
The brake master cylinder
reservoir is filled with DOT
3 brake fluid. SeeEngine
Compartment Overview
on page 6‑16for the
location of the reservoir.
There are only two reasons why the brake fluid level in
the reservoir might go down:
.The brake fluid level goes down because of
normal brake lining wear. When new linings are
installed, the fluid level goes back up.
.A fluid leak in the brake hydraulic system can also
cause a low fluid level. Have the brake hydraulic
system fixed, since a leak means that sooner or
later the brakes will not work well.
6-39
When the Change Engine Oil Soon message
displays, certain services, checks, and inspections are
required. The services described for MaintenanceI
should be performed at every engine oil change.
The services described for Maintenance IIshould be
performed when:
.Maintenance Iwas performed the last time the
engine oil was changed.
.It has been 10 months or more since the Change
Engine Oil Soon message has displayed or since
the last service.
Maintenance I
.Change engine oil and filter. See Engine Oilon
page 6‑18. An Emission Control Service.
.Engine coolant level check. See Engine Coolanton page 6‑31.
.Windshield washer fluid level check. See
Windshield Washer Fluid on page 6‑38.
.Tire inflation check. SeeInflation - Tire Pressureon page 6‑72.
.Tire wear inspection. See Tire Inspection and
Rotation on page 6‑80.
.Rotate tires. See Tire Inspection and Rotationon
page 6‑80.
.Fluids visual leak check (or every 12 months,
whichever occurs first). A leak in any system
must be repaired and the fluid level checked.
.Engine air cleaner filter inspection (vehicles
driven in dusty conditions only). See Engine Air
Cleaner/Filter on page 6‑21.
.Brake system inspection (or every 12 months,
whichever occurs first).
.For vehicles with Allison Transmission®only:
At the first engine oil change only, replace external
transmission filter.
Maintenance II
.Perform all services described in Maintenance I.
.Steering and suspension inspection. Visual
inspection for damaged, loose, or missing parts or
signs of wear.
.Lubricate the front suspension, steering linkage,
and parking brake cable guides. Control arm
ball joints on 2500/3500 series vehicles require
lubrication but should not be lubricated unless their
temperature is−12°C (10°F) or higher, or they
could be damaged. Control arm ball joints on
1500 series vehicles are maintenance‐free.
Vehicles used under severe commercial operating
conditions require lubrication on a regular basis
every 5 000 km/3,000 miles.
7-4