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Towing
Towing Your Vehicle
Consult your dealer/retailer or a professional towing
service to have the vehicle towed. They can provide the
right equipment and know-how to tow it without
damage. SeeRoadside Assistance Program on
page 7-5.
Releasing Air-Operated Parking Brakes
If the vehicle has air brakes, there could be a special
towing problem. If the vehicle has to be towed because
of a complete loss of air pressure from both systems,
the parking brakes will have automatically engaged.The tow operator can release the brakes manually by
using the following steps. Then the vehicle can be towed
with all wheels or only the rear wheels on the ground.
1. Block the wheels of the vehicle.
2. Remove the release stud and nut from the side of
the brake chamber. Some chambers have studs
which are visible at all times.
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3. Remove the rubber
cap from the rear of
the chamber.
4. Put the release stud, nut and flat washer into the
chamber.
5. Turn the stud clockwise a quarter of a turn.6. Turn the stud nut
clockwise several turns
to release the brakes.
Follow the same
procedure to release
the other brake or
brakes.
7. At the repair facility, apply air pressure of at least
70 psi (480 kPa) to the brake chambers, either
from an external air supply or the vehicle’s
air system.
8. Turn the stud nut counterclockwise several turns.
Remove the stud from the chamber.
9. Replace the stud and washer and tighten the nut
into the side of the chamber.
10. Replace the rubber cap.
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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
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Service
For service and parts needs, visit your dealer/retailer.
You will receive genuine GM parts and GM-trained and
supported service people.
Genuine GM parts have one of these marks:
Accessories and Modifications
Adding non-dealer accessories to the vehicle can affect
its performance and safety. Such things as airbags,
braking, stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems like
anti-lock brakes, traction control, and stability control
could be affected. Some non-dealer accessories could
even cause malfunction or damage to parts and systems
and would not be covered by the vehicle warranty.
Damage to vehicle components resulting from the
installation or use of non-GM certified parts, including
control module modifications, are not covered under the
terms of the vehicle warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement and
function with other systems on the vehicle. Your GM
dealer can accessorize the vehicle using genuine
GM Accessories. When you go to your GM dealer and
ask for GM Accessories, you will know that GM-trained
and supported service technicians will perform the
work using genuine GM Accessories.
Also, seeAdding Equipment to Your Airbag-Equipped
Vehicle on page 1-58.
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5. Open the fuel filter vent
valve by turning the
screw counterclockwise
several full turns.
6. Repeatedly push down
on the fuel filter primer
pump with the palm of
your hand. Let the
pump return upward
between pushes.7. Operate the priming pump until a small amount of
fuel seeps from the vent valve. When fuel is seen,
the filter is full of fuel and the system should be
primed.
8. Close the vent valve.
9. Clean any fuel that accumulated on the fuel filter.
10. Start the engine and let it idle for a few minutes.
11. Check the filter for leaks.
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Priming the 7.8L Duramax®Diesel Engine
If the vehicle is equipped with the 7.8L Duramax®diesel
engine, use the following procedure to prime the engine:
1. Make sure there is fuel in the fuel tank.
2. Make sure the specified fuel filter is properly
installed.
3. Make sure the fuel lines are securely connected.4. Make sure the fuel filter is cool to the touch.
5. Use a clean cloth to remove dirt and oil from the
fuel filter head and breather valve.
6. Use the palm of your hand to repeatedly press
and release the plunger at the top of the fuel filter
priming pump. Continue until the plunger resistance
becomes firm. This may take from 20 to 100 times,
depending upon fuel tank location.
7. Turn the fuel filter breather valve screw
counterclockwise several turns to open the
breather valve.
8. Use the palm of your hand to repeatedly press and
release the plunger at the top of the fuel filter
priming pump until fuel begins to seep from the
breather valve.
9. Tighten the fuel filter breather screw to the specified
torque, 4.9Y(43 lbs. in.).
10. Use the palm of your hand to press and release the
plunger at the top of the fuel filter priming pump
about 20 more times. This sends fuel to the engine.
11. Use a clean cloth to remove any fuel from the fuel
filter and surrounding area.
12. Start the engine and allow it to idle for a few
minutes.
13. Check the fuel filter for leakage.
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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.
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Filling the Tank
{CAUTION:
Fuel vapor is highly flammable. It burns violently,
and that can cause very bad injuries. Do not
smoke if you are near fuel or refueling the vehicle.
Keep sparks, flames and smoking materials away
from fuel.
The fuel cap can be on either or both sides of the
vehicle depending on option content.
To take off the cap, turn it slowly counterclockwise. Fuel caps for all
gasoline applications,
and all diesel between
frame rail fuel tank
applications
Fuel caps for all side
mounted diesel
applications
5-20