2008 GMC YUKON DENALI fuel additives

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling the Tank..............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Oil Life System..................................5-16
Engine Air Cleaner/Filter................................5-17
Automatic Transmission Fluid.........................5-20
Engine Coolant.............................................5-23
Coolant Surge Tank Pressure Cap..................5-26
Engine Overheating.......................................5-26
Overheated Engine Protection
Operating Mode........................................5-28Cooling System............................................5-29
Engine Fan Noise.........................................5-34
Power Steering Fluid.....................................5-34
Windshield Washer Fluid................................5-35
Brakes........................................................5-36
Battery........................................................5-39
Jump Starting...............................................5-40
All-Wheel Drive..............................................5-45
Rear Axle.......................................................5-46
Front Axle......................................................5-47
Headlamp Aiming...........................................5-48
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-51
License Plate Lamp......................................5-52
Replacement Bulbs.......................................5-52
Windshield Wiper Blade Replacement..............5-53
Tires..............................................................5-55
Tire Sidewall Labeling...................................5-56
Tire Terminology and Denitions.....................5-58
Ination - Tire Pressure.................................5-60
High-Speed Operation...................................5-62
Tire Pressure Monitor System.........................5-62
Tire Pressure Monitor Operation.....................5-64
Section 5 Service and Appearance Care
5-1

Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle. To help keep the
engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
Gasoline Octane
Use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but
your vehicle’s acceleration could be slightly reduced,
and you might notice a slight audible knocking noise,
commonly referred to as spark knock. If the octane is less
than 87, you might notice a heavy knocking noise when
you drive. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. Otherwise, you could
damage the engine. If you are using gasoline rated at 87
octane or higher and you hear heavy knocking, the
engine needs service.
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. SeeAdditives 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 3-42. 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.
5-5

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.
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.Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of the
emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.
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.
5-6

A
Accessories and Modications............................ 5-3
Adding Equipment to Your Airbag-Equipped
Vehicle.......................................................1-90
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment...........................5-108
Adjustable Throttle and Brake Pedal..................2-29
Air Cleaner/Filter, Engine.................................5-17
Air Conditioning..............................................3-23
Airbag
Passenger Status Indicator...........................3-35
Readiness Light..........................................3-34
Airbag System................................................1-75
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
All-Wheel Drive...............................................5-45
All-Wheel-Drive (AWD) System........................... 4-8
Antenna, Rear Side Window...........................3-119
Antenna, XM™ Satellite Radio Antenna System . . . 3-119
Antilock Brake System (ABS)............................. 4-4
Antilock Brake, System Warning Light................3-40Appearance Care
Aluminum Wheels......................................5-104
Care of Safety Belts...................................5-101
Chemical Paint Spotting..............................5-105
Cleaning Exterior Lamps/Lenses..................5-102
Fabric/Carpet............................................5-100
Finish Care...............................................5-102
Finish Damage..........................................5-105
Instrument Panel, Vinyl, and Other Plastic
Surfaces...............................................5-101
Interior Cleaning..........................................5-98
Leather....................................................5-100
Sheet Metal Damage..................................5-105
Speaker Covers.........................................5-101
Tires........................................................5-104
Underbody Maintenance.............................5-105
Vehicle Care/Appearance Materials...............5-106
Washing Your Vehicle.................................5-102
Weatherstrips............................................5-101
Windshield, Backglass, and Wiper Blades......5-103
Wood Panels............................................5-101
Appointments, Scheduling Service....................... 7-8
Ashtray.........................................................3-22
Audio System.................................................3-73
Audio Steering Wheel Controls....................3-117
Navigation/Radio System, see Navigation
Manual.................................................3-105
Radio Reception........................................3-118
Rear Seat Audio (RSA)...............................3-115
Setting the Clock.........................................3-74
1

Engine
Air Cleaner/Filter.........................................5-17
Check and Service Engine Soon Light............3-42
Coolant......................................................5-23
Coolant Heater............................................2-29
Coolant Temperature Gage...........................3-41
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-12
Exhaust.....................................................2-38
Fan Noise..................................................5-34
Oil .............................................................5-13
Oil Life System...........................................5-16
Overheated Protection Operating Mode...........5-28
Overheating................................................5-26
Running While Parked..................................2-39
Starting......................................................2-27
Entry Lighting.................................................3-20
Event Data Recorders.....................................7-16
Exit Lighting...................................................3-20
Extender, Safety Belt.......................................1-48
Exterior Lamps...............................................3-16
F
Filter
Engine Air Cleaner......................................5-17
Finish Damage.............................................5-105
Flashers, Hazard Warning.................................. 3-6Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-77
Flat Tire, Changing.........................................5-78
Flat Tire, Storing.............................................5-94
Fluid.............................................................5-20
Power Steering...........................................5-34
Windshield Washer......................................5-35
Fog Lamp
Fog ...........................................................3-19
Fog Lamp Light..............................................3-47
Front Axle......................................................5-47
Front Reading Lamps......................................3-20
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-5
Filling a Portable Fuel Container..................... 5-9
Filling the Tank............................................. 5-7
Fuels in Foreign Countries.............................. 5-6
Gage.........................................................3-48
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-5
Low Warning Light.......................................3-48
Fuses
Center Instrument Panel Fuse Block.............5-110
Fuses and Circuit Breakers.........................5-108
Instrument Panel Fuse Block.......................5-109
Underhood Fuse Block...............................5-111
Windshield Wiper.......................................5-108
5