2003 GMC SONOMA oil level

Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Cooling Fan
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.When the engine is cold, the coolant level should be at
least up to the ADD mark. If it isn’t, you may have a
leak at the pressure cap or in the radiator hoses, heater
hoses, radiator, water pump or somewhere else in
the cooling system.
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How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t at the ADD mark, add a 50/50 mixture ofclean,
drinkable waterand DEX-COOL
®engine coolant at the
coolant recovery tank. SeeEngine Coolant on
page 5-25for more information.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn’t get the overheat warning.
Your engine could catchre and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine.
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Checking Brake Fluid
You can check the brakefluid without taking off the cap.
Just look at the brakefluid
reservoir. Thefluid level
should be above MIN.
If it isn’t have your brake
system checked to
see if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over the
MAX mark.
What to Add
When you do need brakefluid, use only DOT-3 brake
fluid. Use new brakefluid from a sealed container
only. SeePart D: Recommended Fluids and Lubricants
on page 6-33.Always clean the brakefluid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind ofuid in your brake
system, your brakes may not work well, or they
may not even work at all. This could cause a
crash. Always use the proper brakeuid.
Notice:
Using the wronguid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they’ll have to be replaced.
Don’t let someone put in the wrong kind ofuid.
If you spill brakeuid on your vehicle’s painted
surfaces, the paintnish can be damaged. Be
careful not to spill brakeuid on your vehicle.
If you do, wash it off immediately. See
“Appearance Care”in the Index.
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Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. Improper vehicle maintenance can
even affect the quality of the air we breathe. Improper
fluid levels or the wrong tire inflation can increase
the level of emissions from your vehicle. To help protect
our environment, and to keep your vehicle in good
condition, be sure to maintain your vehicle properly.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure
to follow scheduled maintenance may not be covered
by warranty.
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2003 - Sonoma OM

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 6-26
andPart C: Periodic Maintenance Inspections on
page 6-31.
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.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-32.
**Drive axle service. See Part D: Recommended Fluids
and Lubricants on page 6-33 for proper lubricant to use:
•Check uid level and add uid as needed. If driving in
dusty areas or when towing a trailer, drain uid and
rell every 15,000 miles (25 000 km).
•If your vehicle has a locking differential, drain uid
and rell at rst engine oil change.
•More frequent lubrication may be required for
heavy-duty or off-road use.
3,000 Miles (5 000 km)
❑Change engine oil andfilter (or every 3 months,
whichever occursfirst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursfirst).(See footnote #.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
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6,000 Miles (10 000 km)
❑Change engine oil andfilter (or every 3 months,
whichever occursfirst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursfirst).(See footnote #.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.(See Footnote **.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote +.)
9,000 Miles (15 000 km)
❑Change engine oil andfilter (or every 3 months,
whichever occursfirst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursfirst).(See footnote #.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
12,000 Miles (20 000 km)
❑Change engine oil andfilter (or every 3 months,
whichever occursfirst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursfirst).(See footnote #.)❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote +.)
15,000 Miles (25 000 km)
❑Change engine oil andfilter (or every 3 months,
whichever occursfirst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursfirst).(See footnote #.)
❑Inspect engine air cleanerfilter. If necessary, replace
thefilter. If vehicle is driven in dusty/dirty conditions,
inspectfilter at every engine oil change. See
Engine Air Cleaner/Filter on page 5-18for more
information.An Emission Control Service.
(See footnote†.)
❑Check rear/front axlefluid level and addfluid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑For Two-Wheel-Drive vehicles only: Clean and
repack the front wheel bearings (or at each
brake relining, whichever occursfirst).
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❑Change automatic transmissionfluid andfilter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C)
or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
If you do not use your vehicle under any of these
conditions, change theuid andlter every 50,000 miles
(83 000 km).
18,000 Miles (30 000 km)
❑Change engine oil and lter (or every 3 months,
whichever occurs rst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occurs rst).(See footnote #.)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote +.)
21,000 Miles (35 000 km)
❑Change engine oil and lter (or every 3 months,
whichever occurs rst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occurs rst).(See footnote #.)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
24,000 Miles (40 000 km)
❑Change engine oil and lter (or every 3 months,
whichever occurs rst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occurs rst).(See footnote #.)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote +.)
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27,000 Miles (45 000 km)
❑Change engine oil andlter (or every 3 months,
whichever occursrst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursrst).(See footnote #.)
❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
30,000 Miles (50 000 km)
❑Change engine oil andlter (or every 3 months,
whichever occursrst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursrst).(See footnote #.)
❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
❑For Two-Wheel-Drive vehicles only: Clean and
repack the front wheel bearings (or at each
brake relining, whichever occursrst).
❑4.3L V6 Engine Only: Replace fuellter.An Emission
Control Service. (See footnote†.)
❑Replace engine air cleanerlter. SeeEngine Air
Cleaner/Filter on page 5-18for more information.
An Emission Control Service.❑Change automatic transmissionuid andlter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C)
or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or
delivery service.
If you do not use your vehicle under any of these
conditions, change theuid andlter every 50,000 miles
(83 000 km).
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-60for proper rotation pattern and additional
information.(See footnote +.)
33,000 Miles (55 000 km)
❑Change engine oil andlter (or every 3 months,
whichever occursrst).An Emission Control Service.
❑Lubricate chassis components (or every 3 months,
whichever occursrst).(See footnote #.)
❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.(See footnote **.)
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2003 - Sonoma OM