open gas tank GMC YUKON 2003 Owner's Manual

Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does not
recommend the use of such gasolines. Fuels containing
MMT can reduce the life of spark plugs and the
performance of the emission control system may be
affected. The malfunction indicator lamp may turn on. If
this occurs, return to your authorized GM dealer for
service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identification number (VIN)
shows the code letter or number that identifies your
engine. You willfind the VIN at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-96.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.Only vehicles that have the 5.3L V8 engine
(VIN Code Z) may use 85% ethanol fuel (E-85).
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help youfind
E-85 fuel. Those stations that do have E-85 should have
a label indicating ethanol content. Do not use the fuel
if the ethanol content isgreaterthan 85%. Your vehicle
may not operate properly if the ethanol content is
greater than 85%.
At a minimum, E-85 should meet ASTM
Specification D 5798.
To insure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E-85, it may be because your E-85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed to
accommodate a mixture of gasoline and E-85 fuel.
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.
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2003 - Yukon/Yukon XL

Fluid
Automatic Transmission................................5-23
Power Steering...........................................5-38
Windshield Washer......................................5-39
FM Stereo....................................................3-123
Fog Lamps
....................................................3-17
Folding the Seatback
.......................................1-16
Folding the Seatbacks
.......................1-9, 1-11, 1-20
Following Distance
..........................................4-69
Footnotes
........................................................ 6-5
Four-Wheel Drive
....................................2-26, 5-51
Front Axle
......................................................5-52
Front Axle Locking Feature
...............................2-26
Front Reading Lamps
......................................3-19
Front Storage Area
.........................................2-54
Frontal Air Bags
.............................................1-76
Fuel
............................................................... 5-4
Additives
...................................................... 5-5
California Fuel
.............................................. 5-5
E-85 (85% Ethanol)
....................................... 5-6
Filling a Portable Fuel Container
....................5-10
Filling Your Tank
........................................... 5-7
Fuels in Foreign Countries
.............................. 5-7
Gage
.........................................................3-52
Gasoline Octane
........................................... 5-4
Gasoline Specifications
.................................. 5-4Fuel (cont.)
Low Warning Light.......................................3-53
System Inspection.......................................6-15
Fuel Information Button....................................3-56
FUEL LEVEL LOW.........................................3-67
Fuses
Fuses and Circuit Breakers...........................5-98
Windshield Wiper.........................................5-97
G
Gage
Engine Coolant Temperature.........................3-46
Fuel..........................................................3-52
Oil Pressure...............................................3-51
Speedometer..............................................3-39
Tachometer.................................................3-39
Transmission Temperature.............................3-46
Voltmeter Gage...........................................3-43
Garage Door Opener.......................................2-50
Gasoline
Octane........................................................ 5-4
Specifications............................................... 5-4
Gate Operator and Canadian Programming........2-53
Getting Familiar with Off-Road Driving................4-26
Glove Box.....................................................2-54
GM Mobility Program for Persons with
Disabilities.................................................... 7-5
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2003 - Yukon/Yukon XL