
Fuel E85 (85% Ethanol)
The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies your
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-103.
If your vehicle has the 5.3L V8 engine (VIN Code 4
only), you can use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85);
also seeFuel on page 5-5. In all other engines, use
only the unleaded gasoline described underGasoline
Octane on page 5-6.
Only vehicles that have the 5.3L V8 engine
(VIN Code 4) can use 85% ethanol fuel (E85). We
encourage the use of E85 in vehicles that are designed
to use it. The ethanol in E85 is a “renewable” fuel,
meaning it is made from renewable sources such as
corn and other crops.Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U. S. Department
of Energy has an alternative fuels website
(www.eere.energy.gov/afdc/infrastructure/locator.html)
that can help you find E85 fuel. Those stations that
do have E85 should have a label indicating ethanol
content. Do not use the fuel if the ethanol content is
greater than 85%.
At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect drivability and could
cause the malfunction indicator lamp to come on.
5-8

Radiator Pressure Cap
The radiator pressure cap is located near the center of
the engine compartment. SeeEngine Compartment
Overview on page 5-14for more information on location.
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 your vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
You will find an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-35for more information.
If Steam Is Coming From Your Engine
{CAUTION:
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. Just 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 your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.
5-26

Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS), if your
vehicle has this feature, is designed to warn the driver
when a low tire pressure condition exists. TPMS sensors
are mounted onto each tire and wheel assembly,
excluding the spare tire and wheel assembly. The TPMS
sensors monitor the air pressure in the vehicle’s tires
and transmits the tire pressure readings to a receiver
located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS will illuminate the
low tire pressure warning
symbol located on the
instrument panel cluster.
At the same time a message to check the pressure in a
specific tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and
the DIC warning message come on at each ignition cycle
until the tires are inflated to the correct inflation pressure.If your vehicle has DIC buttons, tire pressure levels can
be viewed by the driver. For additional information and
details about the DIC operation and displays seeDIC
Operation and Displays on page 3-42andDIC Warnings
and Messages on page 3-49.
The low tire pressure warning light may come on in cool
weather when the vehicle is first started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inflated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct inflation pressure for
your vehicle’s tires when they are cold. SeeLoading
Your Vehicle on page 4-20, for an example of the Tire
and Loading Information label and its location on your
vehicle. Also seeInflation - Tire Pressure on page 5-60.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-68andTires on page 5-53.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.
5-64

If your vehicle does not have RKE, press the Driver
Information Center (DIC) vehicle information button
until the PRESS
VTO RELEARN TIRE POSITIONS
message displays. The horn sounds twice to signal
the receiver is in relearn mode and TIRE LEARNING
ACTIVE message displays on the DIC screen.
If your vehicle does not have RKE or DIC buttons,
press the trip odometer reset stem located on the
instrument panel cluster until the PRESS
VTO
RELEARN TIRE POSITIONS message displays.
The horn sounds twice to signal the receiver is in
relearn mode and TIRE LEARNING ACTIVE
message displays on the DIC screen.
4. Start with the driver side front tire.
5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for five seconds,
or until a horn chirp sounds. The horn chirp, which
may take up to 30 seconds to sound, confirms that
the sensor identification code has been matched to
this tire and wheel position.6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the
procedure in Step 5. The horn sounds two times to
indicate the sensor identification code has been
matched to the driver side rear tire, and that the
TPMS sensor matching process is no longer active.
The TIRE LEARNING ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems.
5-67

If any of the soil remains, a commercial fabric cleaner
or spot lifter may be necessary. When a commercial
upholstery cleaner or spot lifter is to be used, test
a small hidden area for colorfastness first. If the
locally cleaned area gives any impression that a
ring formation may result, clean the entire surface.
After the cleaning process has been completed, a paper
towel can be used to blot excess moisture from the
fabric or carpet.
Instrument Panel, Vinyl, and Other
Plastic Surfaces
A soft cloth dampened with water may be used to
remove dust. If a more thorough cleaning is necessary,
a clean soft cloth dampened with a mild soap solution
can be used to gently remove dust and dirt. Never use
spot lifters or removers on plastic surfaces. Many
commercial cleaners and coatings that are sold to
preserve and protect soft plastic surfaces may
permanently change the appearance and feel of your
interior and are not recommended. Do not use silicone
or wax-based products, or those containing organic
solvents to clean your vehicle’s interior because they
can alter the appearance by increasing the gloss in a
non-uniform manner.Some commercial products may increase gloss on your
instrument panel. The increase in gloss may cause
annoying reflections in the windshield and even make it
difficult to see through the windshield under certain
conditions.
Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather frequent application may be required. See
Recommended Fluids and Lubricants on page 6-14.
5-97