gas type GMC YUKON 2005 Owner's Manual

What Makes an Airbag Inate?
In an impact of sufficient severity, the airbag sensing
system detects that the vehicle is in a crash. For both
frontal and side impact airbags, the sensing system
triggers a release of gas from the inator, which inates
the airbag. The inator, the airbag and related hardware
are all part of the airbag modules. Frontal airbag modules
are located inside the steering wheel and instrument
panel. For vehicles with side impact airbags, the airbag
modules are located in the seatback closest to the
driver’s and/or right front passenger’s door.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The airbag supplements the protection
provided by safety belts. Airbags distribute the force of
the impact more evenly over the occupant’s upper
body, stopping the occupant more gradually. But thefrontal airbags would not help you in many types of
collisions, including rollovers, rear impacts, and many
side impacts, primarily because an occupant’s motion is
not toward the airbag. Side impact airbags would not
help you in many types of collisions, including frontal or
near frontal collisions, rollovers, and rear impacts,
primarily because an occupant’s motion is not toward
those airbags. Airbags should never be regarded
as anything more than a supplement to safety belts, and
then only in moderate to severe frontal or near-frontal
collisions for the driver’s and right front passenger’s
frontal airbags, and only in moderate to severe
side collisions for vehicles with a driver’s and right front
passenger’s side impact airbag.
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Fuel
Gasoline
The 8th digit of your vehicle identication number (VIN)
shows the code letter or number that identies your
engine. You will nd the VIN at the top left of the
instrument panel. SeeVehicle Identication
Number (VIN) on page 5-104.
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 E-85 (85% Ethanol) on page 5-6.Inall
other engines, use only regular unleaded gasoline.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of 87
or higher. If the octane is less than 87, you may get 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 might damage your engine.
A little pinging noise when you accelerate or drive uphill is
considered normal. This does not indicate a problem
exists or that a higher-octane fuel is necessary. If you are
using 87 octane or higher-octane fuel and hear heavy
knocking, your engine needs service.
Gasoline Specications
It is recommended that gasoline meet specications
which were developed by automobile manufacturers
around the world and contained in the World-Wide Fuel
Charter which is available from the Alliance of Automobile
Manufacturers at www.autoalliance.org/fuel_charter.htm.
Gasoline meeting these specications could provide
improved driveability and emission control system
performance compared to other gasoline.
California Fuel
If your vehicle is certied to meet California Emission
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 may be affected. The malfunction indicator
lamp may turn on and your vehicle may fail a
smog-check test. SeeMalfunction Indicator Lamp on
page 3-48. If this occurs, return to your authorized
GM dealer for diagnosis. If it is determined that
the condition is caused by the type of fuel used, repairs
may not be covered by your warranty.
5-5

If the level is below the bottom of the ller plug hole,
you may need to add some lubricant:
When the differential is cold, add enough lubricant
to raise the level to 0 to 3/8 inch (9.5 mm) below
the ller plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level
to the bottom of the ller plug hole.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-13.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-56.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
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