Diesel Particulate Filter
The vehicle has a Diesel Particulate Filter (DPF) as part
of the exhaust system to reduce vehicle emissions. The
DPF requires a unique exhaust tailpipe with an exhaust
cooler. The exhaust cooler mixes air with the exhaust to
lower the temperature before it leaves the tailpipe.
The DPF, the tailpipe, or other exhaust system
components must not be altered. Inspect regularly and
clean any mud or dirt from the exhaust cooler,
especially where the exhaust cooler connects to the
tailpipe and the openings where fresh air enters
the cooler. See “Exhaust System Inspection” underAt
Least Twice a Year on page 6-27.
The DPF will clean itself as part of normal operation.
Several factors including fuel consumed, hours of engine
operation and miles driven are monitored by the Engine
Control Module (ECM). The self cleaning occurs
approximately once per tank of fuel.
During self cleaning, the
green DPF indicator light
will come on. See
Diesel Particulate Filter
Warning Light on
page 3-46.To clean the filter, either drive the vehicle above 30 mph
(50 km/h) to activate self cleaning, or stop the vehicle
and perform the manual cleaning procedure. For
self cleaning, drive until the green DPF indicator light
goes off. This will take approximately 20 minutes. Once
self cleaning has started, drive until the green indicator
light goes off to complete the cleaning in a single
operation if possible.
Extended idling can cause exhaust parts and gases to
become very hot. Keep the exhaust area clear of
material that could ignite or burn. SeeParking Over
Things That Burn on page 2-44for more information.
{CAUTION:
During DPF self cleaning or during extended idling
in P (Park), the exhaust system and exhaust
gases are very hot. Things that burn could touch
hot exhaust parts under the vehicle and ignite.
You or others could be burned. Do not park, or
idle for an extended period of time, near or over
papers, leaves, dry grass, or other things that can
burn. Keep the exhaust area clear of material that
could ignite or burn. SeeParking Over Things
That Burn on page 2-44for more information.
2-46
Low Coolant Warning Light............................3-35
Wait to Start Light........................................3-35
Malfunction Indicator Lamp.............................3-36
Oil Pressure Gage........................................3-38
Low Oil Level Light.......................................3-39
Change Engine Oil Light................................3-39
Engine Overspeed Warning Light....................3-40
Engine Shutdown Warning Light.....................3-40
Transmission Temperature Gage.....................3-40
Exhaust Brake Indicator Light.........................3-41
Differential Lock Indicator Light.......................3-41
Reduced Engine Power Light.........................3-42
Highbeam On Light.......................................3-42
Daytime Running Lamps (DRL)
Indicator Light...........................................3-42
Low Washer Fluid Warning Light.....................3-43
Power Take-Off Light (PTO)...........................3-43Check Gages Warning Light...........................3-43
Fuel Gage...................................................3-44
Water in Fuel Warning Light...........................3-45
Change Fuel Filter Warning Light....................3-45
Diesel Particulate Filter Warning Light..............3-46
Air Filter Restriction Indicator..........................3-46
Air Pressure Gage........................................3-47
Hourmeter Gage...........................................3-47
Audio System(s).............................................3-48
Setting the Clock..........................................3-48
Radio(s)......................................................3-49
Theft-Deterrent Feature..................................3-57
Radio Reception...........................................3-58
Fixed Mast Antenna......................................3-58
Chime Level Adjustment................................3-58
Section 3 Instrument Panel
3-2
Water in Fuel Warning Light
This light is located above
the climate controls in the
center of the instrument
panel.
If your vehicle has the 6.6L DURAMAX
®or a
Caterpillar®diesel engine, this light will come on to
warn you that there is water in the fuel system.
For more information on how this light works, seeWater
in Fuel on page 5-11.
Change Fuel Filter Warning Light
For vehicles with this light,
it is located in the center of
the instrument panel.
If your vehicle has the DURAMAX
®6.6L engine, this
light will come on when the fuel filter needs to be
changed. If your vehicle has the Isuzu 6H 7.8L L6 diesel
engine, this light will come on when water is detected
in the fuel system and when the fuel filter needs to
be changed. SeeFuel Filter Replacement on page 5-18
andWater in Fuel on page 5-11for more information.
3-45
Service............................................................5-3
Accessories and Modifications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-5
Engine Fan Breakage.....................................5-6
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specifications....................................5-7
Additives.......................................................5-7
Diesel Engine Fuel.........................................5-8
What Fuel to Use...........................................5-8
Very Cold Weather Operation.........................5-11
Water in Fuel...............................................5-11
Running Out of Fuel.....................................5-17
Fuel Filter Replacement.................................5-18
Fuels in Foreign Countries.............................5-19
Filling the Tank............................................5-20
Filling a Portable Fuel Container.....................5-22
Checking Things Under the Hood....................5-22
Hood Latches...............................................5-23
Engine Oil (DURAMAX Diesel Engine).............5-24
Engine Oil (Caterpillar Diesel Engine)..............5-27
Engine Oil (Isuzu Diesel Engine).....................5-28
Engine Oil (Gasoline Engine)..........................5-32
Engine Oil Life System (Gasoline Engine)........5-35Engine Oil Life System (DURAMAX/Isuzu
Diesel Engines).........................................5-36
Engine Oil Life System (Caterpillar
Diesel Engine)..........................................5-38
Engine Air Cleaner/Filter................................5-38
Automatic Transmission Fluid.........................5-42
Manual Transmission Fluid.............................5-42
Cooling System............................................5-43
Engine Coolant (Caterpillar Diesel Engines)......5-47
Coolant Surge Tank Pressure Cap..................5-47
Engine Overheating.......................................5-48
Engine Fan Noise.........................................5-49
Power Steering Fluid.....................................5-49
Windshield Washer Fluid................................5-50
Brakes........................................................5-52
Battery........................................................5-61
Jump Starting...............................................5-62
Rear Axle.......................................................5-67
Rear Axle Shift Motor....................................5-68
Four-Wheel Drive............................................5-68
Front Axle......................................................5-69
Noise Control System.....................................5-70
Tampering with Noise Control System
Prohibited.................................................5-70
Bulb Replacement..........................................5-71
Section 5 Service and Appearance Care
5-1
Windshield Wiper Blade Replacement..............5-71
Other Service Items........................................5-72
Fuel Filter....................................................5-72
Primary Fuel Filter and Water Separator..........5-73
Secondary Fuel Filter and Water Separator/
Heater (Caterpillar Diesel)............................5-74
Front Wheel Bearings with
Oil-Filled Hubs..........................................5-75
Tires..............................................................5-76
Inflation - Tire Pressure.................................5-77
Wheel Loading.............................................5-78
Dual Tire Operation.......................................5-78
When It Is Time for New Tires.......................5-78
Buying New Tires.........................................5-79
Wheel Alignment and Tire Balance..................5-80
Tightening the Wheel Nuts.............................5-80
Wheel Replacement......................................5-84
If a Tire Goes Flat........................................5-85
Appearance Care............................................5-87
Interior Cleaning...........................................5-87
Fabric/Carpet...............................................5-88
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-89
Care of Safety Belts......................................5-89
Weatherstrips...............................................5-89
Washing Your Vehicle...................................5-90Cleaning Exterior Lamps/Lenses.....................5-90
Finish Care..................................................5-90
Windshield and Wiper Blades.........................5-91
Aluminum or Chrome-Plated Wheels
and Trim..................................................5-92
Tires...........................................................5-92
Sheet Metal Damage.....................................5-93
Finish Damage.............................................5-93
Underbody Maintenance................................5-93
Chemical Paint Spotting.................................5-93
Vehicle Identification
......................................5-94
Vehicle Identification Number (VIN).................5-94
Service Parts Identification Label.....................5-94
Electrical System............................................5-95
Add-On Electrical Equipment..........................5-95
Headlamp Wiring..........................................5-95
Windshield Wiper Fuses................................5-95
Fusible Links................................................5-95
Power Windows and Other Power Options..........5-96
Fuses and Circuit Breakers............................5-96
Instrument Panel Fuse Block..........................5-96
Underhood Fuse Block..................................5-99
Capacities and Specifications........................5-102
Normal Maintenance Replacement Parts.........5-108
Maintenance Replacement Parts...................5-108
Engine Drive Belt Routing............................5-110
Section 5 Service and Appearance Care
5-2
Fuel Filter Replacement
If you want to change the diesel engine fuel filter
yourself, here is how to do it:
{CAUTION:
Diesel fuel is flammable. It could start a fire if
something ignites it, and you could be burned.
Do not let it get on hot engine parts, and keep
matches or other ignition sources away.
First, drain any water from the filter by following the
water draining procedure earlier in this section.
The vehicle’s engine should be off until the end of this
procedure.If the vehicle has the 6.6L engine, the fuel filter is located
in the engine compartment on the driver side of the
vehicle. If the vehicle has either the 7.2L or 7.8L engine,
the fuel filters are located in the engine compartment
on the driver side of the vehicle, and on the driver side
frame rail in front of the fuel tank.
1. Apply the parking brake.
2. Unplug the water
sensor wire connected
to the fuel filter and
unscrew the filter
element.
3. Remove the filter element. If there is any dirt on the
filter sealing surface, clean it off. Remove and reuse
the water sensor float switch located on the bottom of
the fuel filter.
5-18
4. Install the new filter element.
5. Reinstall and tighten the filter container and
reconnect the water sensor wire to the filter.
6. Use the fuel filter priming procedure earlier in this
section to prime the fuel filter.
7. Tighten the air bleed valve by turning it clockwise
until hand-tight.
8. Start the engine and let it idle for five minutes.
Check the fuel filter and air bleed valve for leaks.
How to Reset Fuel Filter Change
Light - DURAMAX 6.6L (LMM) Engine
The engine controller calculates when to change the fuel
filter based on vehicle and fuel use. Whenever the
fuel filter is changed, reset the fuel filter light so
the engine controller can calculate when the next fuel
filter change is required. If the fuel filter is ever changed
prior to a change fuel filter light being turned on,
reset the fuel filter change light.To reset the Fuel Filter Change light:
1. Turn the ignition key to ON/RUN with the engine off
2. Fully press the accelerator and brake pedals at the
same time for 10 seconds. If the Fuel Filter Change
light flashes for 5 seconds, the system is resetting.
3. Turn the key to OFF.
If the Fuel Filter Change light comes back on when you
start the vehicle, the light has not been reset. Repeat
the procedure. SeeChange Fuel Filter Warning Light on
page 3-45for more information.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by the vehicle warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-19
2. Push the release lever and slide the wiper assembly
toward the driver side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
Other Service Items
Fuel Filter
Fuel Filter/Pressure Regulator
(Gasoline Engines)
The steel fuel filter/pressure regulator is located near
the engine compartment on the driver’s side frame rail.
If your vehicle has a rear steel fuel tank, the fuel
filter/pressure regulator is located near the rear fuel
tank, on the driver’s side frame rail. SeeScheduled
Maintenance on page 6-5for recommended service
intervals.
If your vehicle is equipped with the optional Davco
spin-on type filter, it is located on the driver’s side
frame rail.
Fuel Filter (Diesel Engines)
If you have a diesel engine, your fuel filter is located in
the engine compartment on the driver’s side of the
vehicle, or along the driver’s side frame rail. See “Fuel
Filter Replacement” earlier in this section for further
information.
Also seeScheduled Maintenance on page 6-5for
recommended service intervals.
5-72