maintenance GMC SONOMA 2003 User Guide

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you’ll go to your dealer
for all your service needs. You’ll get genuine GM parts
and GM-trained and supported service people.
We hope you’ll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you’ll
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, seeService
Publications Ordering Information on page 7-9.
Your vehicle may have an air bag system. If it does, see
Servicing Your Air Bag-Equipped Vehicle on page 1-63
before attempting to do your own service work.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeePart E: Maintenance Record on page 6-35.
{CAUTION:
You can be injured and your vehicle could be
damaged ifyou try to do service work on a
vehicle without knowing enough about it.
•Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
CAUTION: (Continued)
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Engine Oil Additives
Don’t add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
If any one of these is true for you, use the short trip/city
maintenance schedule:
•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 or use a carrier on
top of your vehicle.
•The vehicle is used for delivery service, police,
taxi or other commercial application.Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil andfilter
every 3,000 miles (5 000 km) or 3 months—whichever
occursfirst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil andfilter every
7,500 miles (12 500 km) or 12 months—whichever
occursfirst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
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When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter every 15,000 miles
(25 000 km) and replace every 30,000 miles (50 000 km).
If you are driving in dusty/dirty conditions, inspect the
filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To remove either engine air cleaner/filter, do the
following:
1. Remove the fasteners that hold the cover on and
remove the cover
2. Lift out the engine air cleaner/filter, if needed.
3. Insert a new airfilter. SeeNormal Maintenance
Replacement Parts on page 5-96to determine
whichfilter to use.
4. Reinstall the engine air cleaner/filter cover.
Tighten the fasteners to hold the cover in place.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stopame if the engine backres. If it isn’t there
and the engine backres, you could be burned.
Don’t drive with it off, and be careful working on
the engine with the air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging enginere. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when
you’re driving.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 15,000 miles
(25 000 km) 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 thefluid andfilter every
50,000 miles (83 000 km).
SeePart A: Scheduled Maintenance Services
on page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littleuid can damage
your transmission. Too much can mean that some
of theuid could come out and fall on hot engine
part or exhaust system parts, starting are.
Too littleuid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionuid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C)
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3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-33.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.)
If thefluid level is low, add only enough of the proper
fluid to bring the level up to the HOT area for a hot
check. It doesn’t take muchfluid, generally less
than one pint (0.5 L). Don’t overfill.
Notice:We recommend you use onlyuid labeled
DEXRON
®-III, becauseuid with that label is
made especially for your automatic transmission.
Damage caused byuid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under“How to Check”earlier.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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How to Add Fluid
Here’s how to addfluid. Refer to the Maintenance
Schedule to determine what kind offluid to use.
SeePart D: Recommended Fluids and Lubricants on
page 6-33.
1. Remove thefiller plug.
2. Addfluid at thefiller plug hole. Add only enough
fluid to bring thefluid level up to the bottom of the
filler plug hole.
3. Install thefiller plug. Be sure the plug is fully
seated.
Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. The clutch master cylinder reservoir is
filled with hydraulic clutchfluid.
It is not necessary to regularly check clutchfluid unless
you suspect there is a leak in the system. Adding
fluid won’t correct a leak.
Afluid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance Schedule to determine how
often you should check thefluid level in your clutch
master cylinder reservoir and for the properfluid.
SeePart B: Owner Checks and Services on page 6-26
andPart D: Recommended Fluids and Lubricants
on page 6-33.
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Brakes
Brake Fluid
Your brake master cylinder reservoir isfilled with DOT-3
brakefluid. SeeEngine Compartment Overview on
page 5-10for the location of the reservoir.
There are only two reasons why the brakefluid level in
the reservoir might go down. Thefirst is that the
brakefluid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
thefluid level goes back up. The other reason is
thatfluid is leaking out of the brake system.If it is, you should have your brake systemfixed, since
a leak means that sooner or later your brakes won’t
work well, or won’t work at all.
So, it isn’t a good idea to“top off”your brakefluid.
Adding brakefluid won’t correct a leak. If you addfluid
when your linings are worn, then you’ll have too
muchfluid when you get new brake linings. You should
add (or remove) brakefluid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brakeuid, it can spill on
the engine. Theuid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system. See“Checking Brake Fluid”
in this section.
Refer to the Maintenance Schedule to determine when
to check your brakefluid. SeePart C: Periodic
Maintenance Inspections on page 6-31.
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Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top-quality GM brake parts.
When you replace parts of your braking system—for
example, when your brake linings wear down and you
need new ones put in—be sure you get new approved
GM replacement parts. If you don’t, your brakes may no
longer work properly. For example, if someone puts in
brake linings that are wrong for your vehicle, the balance
between your front and rear brakes can change—for the
worse. The braking performance you’ve come to expect
can change in many other ways if someone puts in the
wrong replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-10for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or
more, remove the black, negative (−) cable from
the battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See“Jump Starting”next for
tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature (Non-RDS Radios) on page 3-67or
Theft-Deterrent Feature (RDS Radios) on page 3-67.
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Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
Part A: Scheduled Maintenance Services on page 6-4.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.If the level is below the bottom of thefiller plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of thefiller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-33.
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Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additonal systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart C: Periodic
Maintenance Inspections on page 6-31.
How to Check Lubricant
To get and accurate reading, the vehicle should be on
a level service.
If the level is below the bottom of thefiller plug hole, you’ll
need to add some lubricant. Remove the plug and add
enough lubricant to raise the level to the bottom of the
filler plug hole. Use care not to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-33.
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