Page 249 of 386
5-24
2. Then keep turning the pressure cap slowly, and
remove it.3. Then fill the coolant surge tank with the proper
mixture, to the FULL mark.
Page 250 of 386
5-25
4. With the coolant surge tank pressure cap off, start the
engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fan.
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 slightly above the
FULL mark.
5. Then replace the
pressure cap. Be
sure the pressure
cap is hand
-tight
and fully seated.
Page 251 of 386

5-26
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This
improves fuel economy and reduces fan noise. Under
heavy vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you'd use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place and turn on your
hazard warning flashers. The next part tells you what
to do.
Page 252 of 386

5-27
Changing a Flat Tire
Your truck, when new, did not include tire changing
equipment or a place to store a tire in the vehicle.
Few drivers of these vehicles have the necessary
equipment aboard to be able to change a flat tire safely.
For example, you would need a truck jack that can lift
several thousand pounds and a torque wrench that can
generate several hundred foot
-pounds (Newton-meters)
of twisting force.
CAUTION:
If you try to put air back into a tire that has run
flat, or even a tire that was quite low on air, the
tire can have a sudden air
-out. This could cause
you to lose control of the vehicle and have a
serious crash. Don't refill a flat or very low tire
with air without first having the tire taken off the
wheel and checked for damage.
So if you're stopped somewhere by a flat or damaged
tire or wheel, you should get expert help. See ªRoadside
Assistanceº in the Index.
CAUTION:
Your vehicle, when new, did not include tire
changing equipment or a place to store a tire in
the vehicle. Special tools and procedures are
required if a tire needs to be serviced. If these
tools and procedures aren't used, you or others
could be injured or killed while trying to change
or service a truck tire.
Page 253 of 386

5-28
If You're Stuck: In Sand, Mud, Ice
or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you don't want to spin your
wheels too fast. The method known as ªrockingº can
help you get out when you're stuck, but you must
use caution.
CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you're
stuck, spin the wheels as little as possible. Don't
spin the wheels above 35 mph (55 km/h) as shown
on the speedometer.
NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If your vehicle
has traction control, you should turn your traction
control system off. See ªTraction Control Systemº in the
Index. Then shift back and forth between REVERSE (R)
and a forward gear (or with a manual transmission,
between FIRST (1) or SECOND (2) and
REVERSE (R)), spinning the wheels as little as
possible. Release the accelerator pedal while you shift,
and press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning your wheels
in the forward and reverse directions, you will cause a
rocking motion that may free your vehicle. If that
doesn't get you out after a few tries, you may need to be
towed out. If you do need to be towed out, see ªTowing
Your Vehicleº in the Index.
Page 254 of 386
5-29 Using the Tow Hooks (Option)
If your vehicle is equipped with tow hooks, the hooks
are provided at the front of your vehicle. You may need
to use them if you're stuck off
-road and need to be
pulled to some place where you can continue driving.
CAUTION:
These hooks, when used, are under a lot of force.
Always pull the vehicle straight out. Never pull
on the hooks at a sideways angle. The hooks
could break off and you or others could be
injured from the chain or cable snapping back.
NOTICE:
Never use the tow hooks to tow the vehicle. Your
vehicle could be damaged and it would not be
covered by warranty.
Page 255 of 386

6-
6-1
Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-4 Fuel (Gasoline Engine)
6
-5 Diesel Fuel Requirements and Fuel System
6
-15 Fuels in Foreign Countries (Gasoline Engines)
6
-15 Filling Your Tank
6
-17 Filling a Portable Fuel Container
6
-18 Checking Things Under the Hood
6
-20 Noise Control System
6
-21 Engine Oil (Gasoline Engines)
6
-27 Engine Oil (Caterpillar Diesel Engines)
6
-27 Engine Oil (DURAMAX Diesel)
6
-30 Engine Air Cleaner/Filter
6
-32 Automatic Transmission Fluid
6
-32 Manual Transmission Fluid
6
-34 Rear Axle
6
-34 Rear Axle Shift Motor (Option)
6
-35 Engine Coolant
6
-38 Engine Coolant (Caterpillar Diesel Engine)6
-38 Surge Tank Pressure Cap
6
-39 Power Steering Fluid
6
-40 Windshield Washer Fluid
6
-41 Brakes
6
-52 Battery
6
-54 Other Service Items
6
-58 Tires
6
-67 Appearance Care
6
-68 Cleaning the Inside of Your Vehicle
6
-71 Cleaning the Outside Your Vehicle
6
-75 GM Vehicle Care/Appearance Materials
6
-76 Vehicle Identification Number (VIN)
6
-76 Service Statement
6
-77 Service Parts Identification Label
6
-77 Electrical System
6
-86 Capacities and Specifications
6
-90 Normal Maintenance Replacement Parts
Page 256 of 386

6-2
Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you'll go to your dealer for
all your service needs. You'll get genuine GM parts and
GM
-trained and supported service people.
We hope you'll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you'll
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, see ªService
and Owner Publicationsº in the Index.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. See ªMaintenance Recordº in the Index.
CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off. You could be hurt.