2008 GMC YUKON fuel additives

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuel E85 (85% Ethanol)..................................5-7
Fuels in Foreign Countries...............................5-8
Filling the Tank..............................................5-9
Filling a Portable Fuel Container.....................5-11
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-19
Automatic Transmission Fluid
(4-Speed Transmission)..............................5-22
Automatic Transmission Fluid
(6-Speed Transmission)..............................5-24
Engine Coolant.............................................5-28Coolant Surge Tank Pressure Cap..................5-31
Engine Overheating.......................................5-31
Overheated Engine Protection
Operating Mode........................................5-33
Cooling System............................................5-34
Engine Fan Noise.........................................5-39
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery
........................................................5-45
Jump Starting...............................................5-46
Rear Axle.......................................................5-52
Four-Wheel Drive............................................5-54
Front Axle......................................................5-55
Headlamp Aiming...........................................5-56
Bulb Replacement..........................................5-59
Halogen Bulbs..............................................5-59
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-60
License Plate Lamp......................................5-61
Replacement Bulbs.......................................5-61
Windshield Wiper Blade Replacement..............5-62
Tires..............................................................5-64
Tire Sidewall Labeling...................................5-65
Tire Terminology and Denitions.....................5-69
Ination - Tire Pressure.................................5-72
Section 5 Service and Appearance Care
5-1

Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or
3.511 in Canada. Some gasolines contain an
octane-enhancing additive called methylcyclopentadienyl
manganese tricarbonyl (MMT). We recommend
against the use of gasolines containing MMT. See
Additives on page 5-6for additional information.
California Fuel
If your vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance might be affected. The malfunction
indicator lamp could turn on and your vehicle might fail
a smog-check test. SeeMalfunction Indicator Lamp
on page 3-48. If this occurs, return to your authorized
dealer/retailer for diagnosis. If it is determined that
the condition is caused by the type of fuel used, repairs
might not be covered by your warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In
most cases, you should not have to add anything to the
fuel. However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations. To help
keep fuel injectors and intake valves clean, or if
your vehicle experiences problems due to dirty injectors
or valves, look for gasoline that is advertised as TOP
TIER Detergent Gasoline. Also, your dealer/retailer has
additives that will help correct and prevent most
deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.
5-6

At a minimum, E85 should meet ASTM Specication
D 5798. By denition, 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 specications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according to
ASTM specication D 5798. If you have trouble starting
on E85, it could be because the E85 fuel is not properly
formulated for your climate. If this happens, switching to
gasoline or adding gasoline to the fuel tank can improve
starting. For good starting and heater efficiency below
32°F (0°C), the fuel mix in the fuel tank should contain no
more than 70% ethanol. It is best not to alternate
repeatedly between gasoline and E85. If you do switch
fuels, it is recommended that you add as much fuel as
possible — do not add less than three gallons (11 L)
when refueling. You should drive the vehicle immediately
after refueling for at least seven miles (11 km) to allow the
vehicle to adapt to the change in ethanol concentration.
E85 has less energy per gallon than gasoline, so you will
need to rell the fuel tank more often when using E85
than when you are using gasoline. SeeFilling the
Tank on page 5-9.Notice:Some additives are not compatible with
E85 fuel and can harm your vehicle’s fuel system.
Do not add anything to E85. Damage caused by
additives would not be covered by your new vehicle
warranty.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under your
warranty.
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 nd. 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 your 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.
5-8

A
Accessories and Modications............................ 5-3
Adding a Snow Plow or Similar Equipment.........4-41
Adding Equipment to Your Airbag-Equipped
Vehicle.......................................................1-90
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment...........................5-117
Adjustable Throttle and Brake Pedal..................2-29
Air Cleaner/Filter, Engine.................................5-19
Air Conditioning......................................3-23, 3-26
Airbag
Passenger Status Indicator...........................3-41
Readiness Light..........................................3-40
Airbag System................................................1-76
What Will You See After an Airbag Inates?....1-84
When Should an Airbag Inate?....................1-81
Where Are the Airbags?...............................1-78
Airbag Systems
Adding Equipment to Your Airbag-Equipped
Vehicle...................................................1-90
How Does an Airbag Restrain?......................1-83
Passenger Sensing System...........................1-85
Servicing Your Airbag-Equipped Vehicle..........1-90
What Makes an Airbag Inate?......................1-83
Antenna, Rear Side Window...........................3-130
Antenna, XM™ Satellite Radio Antenna
System.....................................................3-130Antilock Brake System (ABS)............................. 4-5
Antilock Brake, System Warning Light................3-46
Appearance Care
Aluminum or Chrome-Plated Wheels.............5-113
Care of Safety Belts...................................5-111
Chemical Paint Spotting..............................5-115
Cleaning Exterior Lamps/Lenses..................5-112
Fabric/Carpet............................................5-109
Finish Care...............................................5-112
Finish Damage..........................................5-114
Instrument Panel, Vinyl, and Other Plastic
Surfaces...............................................5-110
Interior Cleaning........................................5-108
Leather
....................................................5-110
Sheet Metal Damage..................................5-114
Tires........................................................5-114
Underbody Maintenance.............................5-114
Vehicle Care/Appearance Materials...............5-115
Washing Your Vehicle.................................5-111
Weatherstrips............................................5-111
Windshield, Backglass, and Wiper Blades......5-113
Appointments, Scheduling Service....................... 7-9
Ashtray.........................................................3-23
Audio System.................................................3-81
Audio Steering Wheel Controls....................3-128
Navigation/Radio System, see Navigation
Manual.................................................3-114
Radio Reception........................................3-129
1

Engine
Air Cleaner/Filter.........................................5-19
Check and Service Engine Soon Light............3-48
Coolant......................................................5-28
Coolant Heater............................................2-30
Coolant Temperature Gage...........................3-47
Drive Belt Routing.......................................6-16
Engine Compartment Overview......................5-14
Exhaust.....................................................2-47
Fan Noise..................................................5-39
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheated Protection Operating Mode...........5-33
Overheating................................................5-31
Running While Parked..................................2-48
Starting......................................................2-28
Entry Lighting.................................................3-20
Event Data Recorders.....................................7-16
Exit Lighting...................................................3-20
Extender, Safety Belt.......................................1-50
Exterior Lamps...............................................3-16
F
Filter
Engine Air Cleaner......................................5-19
Finish Damage.............................................5-114
Flashers, Hazard Warning.................................. 3-6
Flash-to-Pass................................................... 3-9Flat Tire........................................................5-87
Flat Tire, Changing.........................................5-88
Flat Tire, Storing...........................................5-103
Fluid.....................................................5-22, 5-24
Power Steering...........................................5-39
Windshield Washer......................................5-40
Fog Lamp
Fog ...........................................................3-19
Fog Lamp Light..............................................3-53
Four-Wheel Drive....................................2-38, 5-54
Front Axle......................................................5-55
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-6
E85 (85% Ethanol)........................................ 5-7
Filling a Portable Fuel Container....................5-11
Filling the Tank............................................. 5-9
Fuels in Foreign Countries.............................. 5-8
Gage.........................................................3-54
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-6
Low Warning Light.......................................3-55
Fuses
Center Instrument Panel Fuse Block.............5-119
Fuses and Circuit Breakers.........................5-117
Instrument Panel Fuse Block.......................5-118
Underhood Fuse Block...............................5-120
Windshield Wiper.......................................5-117
5