gas type GMC SIERRA 2007 Owner's Manual

The threshold level can vary, however, with
specic vehicle design, so that it can be somewhat
above or below this range. Vehicle’s with dual
stage airbags also have a sensor which enables
the sensing system to monitor the position of
the driver seat. The seat position sensor provides
information which is used to determine if the
airbags should deploy at a reduced level or at full
deployment.
What Makes an Airbag Inate?
In an impact of sufficient severity, the airbag
sensing system detects that the vehicle is
in a crash. In the case of a roof-mounted rollover
airbag, the sensing system detects that the
vehicle is about to roll over or has been in a severe
frontal impact or a moderate to severe side
impact. The sensing system triggers a release of
gas from the inator, which inates the airbag.
The inator, airbag, and related hardware are all
part of the airbag modules inside the steering
wheel and in the instrument panel in front of the
right front passenger. For vehicles with
roof-mounted rollover airbags, the airbag modules
are located in the ceiling of the vehicle, near
the side windows.
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.
Airbags supplement 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
the frontal 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.
Roof-mounted rollover airbags would not help you
in many types of collisions, including many
frontal or near frontal collisions, and rear impacts.
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 or rollovers for vehicles
with roof-mounted rollover airbags.
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Gasoline Octane
Use regular unleaded gasoline with a posted
octane rating of 87 or higher. If the octane rating
is less than 87, you might notice an audible
knocking noise when you drive, commonly referred
to as spark knock. If this occurs, use a gasoline
rated at 87 octane or higher as soon as possible. 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 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 490for 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 may be affected. The malfunction
indicator lamp may turn on and your vehicle may
fail a smog-check test. SeeMalfunction Indicator
Lamp on page 260. 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.
489

{CAUTION:
If a re starts while you are refueling, do
not remove the nozzle. Shut off the ow of
fuel by shutting off the pump or by
notifying the station attendant. Leave the
area immediately.
Notice:If you need a new fuel cap, be sure to
get the right type. Your dealer/retailer can
get one for you. If you get the wrong type, it
may not t properly. This may cause your
malfunction indicator lamp to light and may
damage your fuel tank and emissions system.
SeeMalfunction Indicator Lamp on page 260.
Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it
is in your vehicle. Static electricity
discharge from the container can ignite the
gasoline vapor. You can be badly burned
and your vehicle damaged if this occurs.
To help avoid injury to you and others:
Dispense gasoline only into approved
containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup
bed, or on any surface other than the
ground.
Bring the ll nozzle in contact with the
inside of the ll opening before
operating the nozzle. Contact should
be maintained until the lling is
complete.
Do not smoke while pumping gasoline.
Do not use a cellular phone while
pumping gasoline.
495

Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3047
Back-up Lamp* 1156
Cargo Lamp and Center
High-Mounted Stoplamp (CHMSL)912
Daytime Running Lamps (DRL) 4114K
Fender Marker and Front Roof
MarkerW5WLL
Front Parking and Turn Lamp 3457A
License Plate Lamp 168
Rear Marker Lamp, Taillamp and
Stoplamp*3047
Rear Turn Signal Lamp 3047
Sidemarker Lamp 194
Stoplamp/Turn Signal Lam/Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed here, contact
your dealer/retailer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for
wear or cracking. SeeScheduled Maintenance
(Gasoline Engine) on page 623.
Replacement blades come in different types and
are removed in different ways. To replace the
wiper blade assembly, do the following:
1. Pull the windshield wiper arm connector away
from the windshield.
2. Squeeze the grooved areas on each side of
the blade, and rotate the blade assembly
away from the arm connector.
549

How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are
properly inated simply by looking at them. Radial
tires may look properly inated even when
they’re underinated. Check the tire’s ination
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
Dual Tire Operation
When the vehicle is new, or whenever a wheel,
wheel bolt or wheel nut is replaced, check the
wheel nut torque after 100, 1,000 and 6,000 miles
(160, 1 600 and 10 000 km) of driving. For proper
torque and wheel nut tightening information, see
Removing the Spare Tire and Tools on page 578.
The outer tire on a dual wheel setup generally
wears faster than the inner tire. Your tires will wear
more evenly and last longer if you rotate the
tires periodically, seeTire Inspection and Rotation
on page 565. Also seeScheduled Maintenance
(Gasoline Engine) on page 623.
{CAUTION:
If you operate your vehicle with a tire that
is badly underinated, the tire can
overheat. An overheated tire can lose air
suddenly or catch re. You or others
could be injured. Be sure all tires
(including the spare) are properly inated.
SeeInation - Tire Pressure on page 559, for
information on proper tire ination.
560