Page 417 of 474
FusesUsage
1 Fuel Pump
2 Left Park Lamp
3 Not Used
4 Right Park Lamp
FusesUsage
5Engine Control Module (ECM)/
Transmission Control Module (TCM)
6 Memory Module
7 Not Used
6-115
Page 421 of 474
ApplicationCapacities
English Metric
Transmission Fluid - Bottom Pan Removal
3.9L V6 Engine 7.4 qt 7.0 L
4.6L V8 Engine 7.4 qt 7.0 L
Wheel Nut Torque 100 lb ft 140 Y
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual.
Recheck fluid level after filling.
Engine Specifications
Engine VIN CodeTransmissions Spark Plug Gap
3.9L V6 Engine 1Automatic 0.040 in (1.01 mm)
3.9L V6 Engine MAutomatic0.040 in (1.01 mm)
4.6L V8 Engine 9Automatic 0.050 in (1.27 mm)
6-119
Page 427 of 474

Additional Required Services
At Each Fuel Stop
.Engine oil level check. SeeEngine Oilon
page 6‑17.
.Engine coolant level check. See Engine Coolant
(4.6L Engine)on page 6‑27or Engine Coolant
(3.9L Engine) on page 6‑31.
.Windshield washer fluid level check. See
Windshield Washer Fluid on page 6‑39.
Once a Month
.Tire inflation check. See Inflation - Tire Pressureon page 6‑65.
.Tire wear inspection. See Tire Inspection and
Rotation on page 6‑71.
Once a Year
.Starter switch check. See Owner Checks and
Services on page 7‑8.
.Parking brake and automatic transmission P (Park)
mechanism check. See Owner Checks and
Services on page 7‑8.
.Automatic transmission shiftlock control system
check. See Owner Checks and Serviceson
page 7‑8.
.Ignition transmission lock check. See Owner
Checks and Services on page 7‑8.
.Engine cooling system and pressure cap pressure
check. Radiator and air conditioning condenser
outside cleaning. See Cooling System
on
page 6‑26.
.Exhaust system and nearby heat shields
inspection for loose or damaged components.
.Accelerator pedal check for damage, high effort,
or binding. Replace if needed.
.If the vehicle has a Tire Sealant and Compressor
Kit, check the sealant expiration date printed on
the instruction label of the kit. See Tire Sealant and
Compressor Kit on page 6‑82.
7-5
Page 428 of 474

First Engine Oil Change After Every
40 000 km/25,000 Miles
.Fuel system inspection for damage or leaks.
First Engine Oil Change After Every
80 000 km/50,000 Miles
.Engine air cleaner filter replacement. SeeEngine
Air Cleaner/Filter on page 6‑21.
.Automatic transmission fluid change (severe
service) for vehicles mainly driven in heavy city
traffic in hot weather, in hilly or mountainous
terrain, when frequently towing a trailer, or used for
taxi, police, or delivery service. See Automatic
Transmission Fluid on page 6‑23.
First Engine Oil Change After Every
160 000 km/100,000 Miles
.Automatic transmission fluid change (normal
service). See Automatic Transmission Fluidon
page 6‑23.
.Spark plug replacement. An Emission Control
Service.
First Engine Oil Change After Every
240 000 km/150,000 Miles
.Engine cooling system drain, flush, and refill,
cooling system and cap pressure check, and
cleaning of outside of radiator and air conditioning
condenser (or every 5 years, whichever occurs
first). See Engine Coolant (4.6L Engine)
on
page 6‑27or Engine Coolant (3.9L Engine)on
page 6‑31. An Emission Control Service.
.Engine accessory drive belt inspection for fraying,
excessive cracks, or obvious damage and
replacement, if needed. An Emission Control
Service.
7-6
Page 430 of 474

Owner Checks and Services
Starter Switch Check
{WARNING:
When you are doing this inspection, the vehicle
could move suddenly. If the vehicle moves, you or
others could be injured.
1. Before starting this check, be sure there is enough room around the vehicle.
2. Firmly apply both the parking brake and the regular brake. See Parking Brake on page 3‑26.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle should start only in P (Park) or N (Neutral). If the
vehicle starts in any other position, contact your
dealer for service.
Automatic Transmission Shift Lock
Control System Check
{WARNING:
When you are doing this inspection, the vehicle
could move suddenly. If the vehicle moves, you or
others could be injured.
1. Before starting this check, be sure there is enough room around the vehicle. It should be parked on a
level surface.
2. Firmly apply the parking brake. See Parking Brake
on page 3‑26.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the ignition to ON/RUN, but do not start the engine. Without applying the
regular brake, try to move the shift lever out of
P (Park) with normal effort. If the shift lever moves
out of P (Park), contact your dealer for service.
7-8
Page 431 of 474

Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition to LOCK/OFF in each shift lever position.
.The ignition should turn to LOCK/OFF only when
the shift lever is in P (Park).
.The ignition key should come out only in
LOCK/OFF.
Contact your dealer if service is required.
Parking Brake and Automatic
Transmission P (Park) Mechanism
Check
{WARNING:
When you are doing this check, the vehicle could
begin to move. You or others could be injured and
property could be damaged. Make sure there is
room in front of the 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 the transmission in
N (Neutral), slowly remove foot pressure from the
regular brake pedal. Do this until the vehicle is held
by the parking brake only.
.To check the P (Park) mechanism's holding ability:
With the engine running, shift to P (Park). Then
release the parking brake followed by the regular
brake.
Contact your dealer if service is required.
Recommended Fluids and
Lubricants
Fluids and lubricants identified below by name, part
number, or specification can be obtained from your
dealer.
Usage Fluid/Lubricant
Engine Oil Engine oil which meets GM Standard
GM6094M and displays the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol.
To determine the proper viscosity for
your vehicle's engine, see
Engine Oil
on page 6‑17.
7-9
Page 432 of 474

UsageFluid/Lubricant
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. See
Engine Coolant
(4.6L Engine)on page 6‑27or
Engine Coolant (3.9L Engine)on
page 6‑31.
Hydraulic Brake System DOT 3 Hydraulic Brake Fluid
(GM Part No. U.S. 88862806,
in Canada 88862807).
Windshield Washer Optikleen
®Washer Solvent.
Parking Brake Cable Guides Chassis Lubricant
(GM Part No. U.S. 12377985,
in Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Power Steering System GM Power Steering Fluid
(GM Part No. U.S. 89021184,
in Canada 89021186).
Usage
Fluid/Lubricant
Automatic
Transmission DEXRON®-VI Automatic Transmission
Fluid.
Key Lock
Cylinders Multi-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241,
in Canada 10953474).
Hood Latch Assembly,
Secondary
Latch, Pivots,
Spring Anchor, and
Release Pawl Lubriplate Lubricant Aerosol
(GM Part No. U.S. 12346293,
in Canada 992723) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Hood and Door Hinges Multi-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241,
in Canada 10953474).
Weatherstrip Conditioning Weatherstrip Lubricant
(GM Part No. U.S. 3634770,
in Canada 10953518) or
Dielectric Silicone Grease
(GM Part No. U.S. 12345579,
in Canada 992887).
7-10
Page 455 of 474

Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your
vehicle has a safety defect, notify Transport Canada
immediately, in addition to notifying General Motors of
Canada Limited. Call them at 1-800-333-0510 or
write to:Transport Canada
Road Safety Branch
2780 Sheffield Road
Ottawa, Ontario K1B 3V9
Reporting Safety Defects to General
Motors
In addition to notifying NHTSA (or Transport Canada) in
a situation like this, please notify General Motors.
Call 1-800-521-7300, or write:Buick Customer Assistance Center
P.O. Box 33136
Detroit, MI 48232-5136 In Canada, call 1-800-263-3777 (English) or
1-800-263-7854 (French), or write:
General Motors of Canada Limited
Customer Communication Centre, CA1-163-005
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.
Service Bulletins
Service Bulletins give additional technical service
information needed to knowledgeably service
General Motors cars and trucks. Each bulletin contains
instructions to assist in the diagnosis and service of
your vehicle.
8-17