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Ignition Transmission Lock Check
While parked, and with the parking brake set, try
to turn the ignition to LOCK in each shift lever
position.
The ignition should turn to LOCK only when
the shift lever is in PARK (P).
The key should come out only in LOCK.
Contact your GM Goodwrench
®dealer if service is
required.
Parking Brake and Automatic Transmission
Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your
vehicle could begin to move. You or others
could be injured and property could be
damaged. Make sure there is room in front
of your vehicle in case it begins to roll.
Be ready to apply the regular brake at
once should the vehicle begin to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular
brake, set the parking brake.
To check the parking brake’s holding ability:
With the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure
from the regular brake pedal. Do this until the
vehicle is held by the parking brake only.
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To check the PARK (P) mechanism’s holding
ability: With the engine running, shift to
PARK (P). Then release the parking brake
followed by the regular brake.
Contact your GM Goodwrench
®dealer if service
is required.
Hood and Liftgate Support Gas Strut
Service
Visually inspect gas strut for signs of wear,
corrosion, cracks, loss of lubricant, or other
damage. Check the hold open ability of gas strut.
If necessary, replace with genuine GM parts.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take
care to clean thoroughly any areas where mud and
other debris can collect.
Recommended Fluids and
Lubricants
Fluids and lubricants identi ed below by name,
part number, or speci cation may be obtained
from your dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certi ed for Gasoline Engines
starburst symbol. GM Goodwrench
®
oil meets all the requirements for
your vehicle. To determine the
proper viscosity for your vehicle’s
engine, seeEngine Oil on page 432.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant on
page 445.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake uid.
Windshield
WasherGM Optikleen
®Washer Solvent.
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Page 582 of 608

Vehicle Data Collection and Event
Data Recorders
Your vehicle, like other modern motor vehicles, has
a number of sophisticated computer systems that
monitor and control several aspects of the vehicle’s
performance. Your vehicle uses on-board vehicle
computers to monitor emission control components
to optimize fuel economy, to monitor conditions for
airbag deployment and, if so equipped, to provide
anti-lock braking and to help the driver control
the vehicle in difficult driving situations. Some
information may be stored during regular operations
to facilitate repair of detected malfunctions; other
information is stored only in a crash event by
computer systems, such as those commonly called
event data recorders (EDR).In a crash event, computer systems, such as the
Airbag Sensing and Diagnostic Module (SDM)
in your vehicle may record information about the
condition of the vehicle and how it was operated,
such as data related to engine speed, brake
application, throttle position, vehicle speed, safety
belt usage, airbag readiness, airbag performance,
and the severity of a collision. If your vehicle is
equipped with StabiliTrak
®, steering performance,
including yaw rate, steering wheel angle, and
lateral acceleration, is also recorded. This
information has been used to improve vehicle
crash performance and may be used to improve
crash performance of future vehicles and
driving safety. Unlike the data recorders on many
airplanes, these on-board systems do not
record sounds, such as conversation of vehicle
occupants.
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Reporting Safety Defects to
General Motors
In addition to notifying NHTSA (or Transport
Canada) in a situation like this, we certainly hope
you’ll notify us. Please call us at 1-800-GMC-8782
(1-800-462-8782), or write:
GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, please call us at 1-800-263-3777
(English) or 1-800-263-7854 (French).
Or, write:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle
suspension, brakes, electrical, steering, body, etc.
Transmission, Transaxle, Transfer
Case Unit Repair Manual
This manual provides information on unit
repair service procedures, adjustments, and
speci cations for GM transmissions, transaxles,
and transfer cases.
589
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