2004 GMC SONOMA belt

Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.
Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-67.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation motor vehicle safety
standards. The DOT code includes the Tire Identification
Number (TIN), an alphanumeric designator which can
also identify the tire manufacturer, production plant,
brand and date of production.GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-45.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-45.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-45.
Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward when
mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
There are 6.9 kPa’s to one psi.
Light Truck (LT-Metric) Tire:A tire used on light duty
trucks and some multipurpose passenger vehicles.
Load Index:An assigned number ranging from 1 to 279
that corresponds to the load carrying capacity of
a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inflated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at the
maximum permissible inflation pressure for that tire.
5-65

Buying New Tires
To find out what kind and size of tires you need, look at
the Certification/Tire label or Tire and Loading
Information label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
GM recommends that you get tires with that same
TPC Spec number. That way your vehicle will continue
to have tires that are designed to give proper
endurance, handling, speed rating, traction, ride and
other things during normal service on your vehicle.
If your tires have an all-season tread design, the TPC
number will be followed by an “MS” (for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. It’s all right to drive with your
compact spare (if you have one). It was
developed for use on your vehicle.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
5-70

Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth at least every six
months. During very cold, damp weather more frequent
application may be required. SeePart D: Recommended
Fluids and Lubricants on page 6-32.
Cleaning the Outside of Your
Vehicle
The paint finish on your vehicle provides beauty, depth
of color, gloss retention and durability.
Washing Your Vehicle
The best way to preserve your vehicle’s finish is to
keep it clean by washing it often with lukewarm or
cold water.
Do not wash your vehicle in the direct rays of the sun.
Use a car washing soap. Do not use strong soaps
or chemical detergents. Be sure to rinse the vehicle well,
removing all soap residue completely. You can get
GM-approved cleaning products from your dealer. See
Vehicle Care/Appearance Materials on page 5-93.
Do not use cleaning agents that are petroleum based,
or that contain acid or abrasives. All cleaning agents
should be flushed promptly and not allowed to dry on the
surface, or they could stain. Dry the finish with a soft,
clean chamois or an all-cotton towel to avoid surface
scratches and water spotting.
High pressure car washes may cause water to enter
your vehicle.
5-89

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Selecting the Right Schedule...........................6-5
Short Trip/City Scheduled Maintenance..............6-6
Long Trip/Highway Scheduled Maintenance......6-17
Part B: Owner Checks and Services................6-25
At Each Fuel Fill..........................................6-25
At Least Once a Month.................................6-25
At Least Twice a Year...................................6-26
At Least Four Times a Year...........................6-27At Least Once a Year...................................6-27
Part C: Periodic Maintenance Inspections.........6-30
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-30
Exhaust System Inspection............................6-30
Fuel System Inspection..................................6-30
Engine Cooling System Inspection...................6-30
Throttle System Inspection.............................6-31
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection.......................................6-31
Brake System Inspection................................6-31
Part D: Recommended Fluids and Lubricants. . . .6-32
Normal Maintenance Replacement Parts..........6-34
Engine Drive Belt Routing..............................6-35
Part E: Maintenance Record...........................6-36
Section 6 Maintenance Schedule
6-1

Selecting the Right Schedule
First you will need to decide which of the two schedules
is right for your vehicle. Here is how to decide which
schedule to follow:
Short Trip/City Denition
Follow the Short Trip/City Scheduled Maintenance if any
one of these conditions is true for your vehicle:
•Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
•Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
•You frequently tow a trailer.
•If the vehicle is used for delivery service, police,
taxi or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km):Engine Oil and Filter
Change (or 3 months, whichever occurs first). Chassis
Lubrication (or 3 months, whichever occurs first).
Drive Axle Service.
Every 6,000 Miles (10 000 km):Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Automatic Transmission Service
(severe conditions only).
Every 30,000 Miles (50 000 km):Engine Air Cleaner
Filter Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150 000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
first). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
6-5

Long Trip/Highway Denition
Follow this scheduled maintenanceonlyif none of the
conditions from the Short Trip/City Scheduled
Maintenance are true. Do not use this schedule if the
vehicle is used for trailer towing, driven in a dusty area
or used off paved roads. Use the Short Trip/City
schedule for these conditions
Driving a vehicle with a fully warmed engine under
highway conditions will cause engine oil to break down
slower.
Long Trip/Highway Intervals
Every 7,500 Miles (12 500 km):Engine Oil and Filter
Change (or every 12 months, whichever occurs
first). Chassis Lubrication (or 12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Automatic Transmission Service
(severe conditions only).
Every 30,000 Miles (50 000 km):Fuel Filter
Replacement. Engine Air Cleaner Filter Replacement.
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
first). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
Short Trip/City Scheduled
Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
SeePart B: Owner Checks and Services on page 6-25
andPart C: Periodic Maintenance Inspections on
page 6-30.
6-6

99,000 Miles (165 000 km)
❑Change engine oil and filter (or every 3 months,
whichever occurs first).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occurs first).(See footnote #.)
❑Check rear/front axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
100,000 Miles (166 000 km)
❑Inspect spark plug wires.An Emission Control
Service.
❑Replace spark plugs.An Emission Control Service.
❑If you have not used your vehicle under severe
service conditions listed previously and, therefore,
have not changed your automatic transmission fluid,
change both the fluid and filter.
❑Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)
❑Drain, flush and refill cooling system (or every
60 months since last service, whichever occurs first).
SeeEngine Coolant on page 5-23for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test cooling system and
pressure cap.An Emission Control Service.
❑Inspect engine accessory drive belt.An Emission
Control Service.
Long Trip/Highway Scheduled
Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
SeePart B: Owner Checks and Services on page 6-25
andPart C: Periodic Maintenance Inspections on
page 6-30.
Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
#Lubricate the front suspension, ball joints, steering
linkage, parking brake cable guides, propshaft splines,
universal joints, constant velocity joint and brake
pedal springs.
6-17

97,500 Miles (162 500 km)
❑Change engine oil and filter (or every 12 months,
whichever occurs first).An Emission Control
Service.
❑Lubricate chassis components (or every 12 months,
whichever occurs first).(See footnote #.)
❑Check rear/front axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-68for proper rotation pattern and additional
information.(See footnote +.)
100,000 Miles (166 000 km)
❑Inspect spark plug wires.An Emission Control
Service.
❑Replace spark plugs.An Emission Control Service.
❑If you have not used your vehicle under severe
service conditions listed previously and, therefore,
have not changed your automatic transmission fluid,
change both the fluid and filter.
❑Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)
❑Drain, flush and refill cooling system (or every
60 months since last service, whichever occurs first).
SeeEngine Coolant on page 5-23for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.An Emission Control Service.
❑Inspect engine accessory drive belt.An Emission
Control Service.
6-24