warning GMC SONOMA 2003 Owner's Guide

Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies
in your vehicle.Include an ice scraper, a small brush or broom, a
supply of windshield washeruid, a rag, some winter
outer clothing, a small shovel, aashlight, a red
cloth and a couple of reective warning triangles.
And, if you will be driving under severe conditions,
include a small bag of sand, a piece of old carpet or a
couple of burlap bags to help provide traction. Be
sure you properly secure these items in your vehicle.
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Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
If you have an automatic transmission, you should use
THIRD (3) when towing a trailer. Operating your
vehicle in THIRD (3) when towing a trailer will minimize
heat buildup and extend the life of your transmission.
Or, if you have a manual transmission, it’s better not to
use FIFTH (5). Just drive in FOURTH (4) (or, as you
need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P)
(or the manual transmission out of gear and the parking
brake applied) for a few minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 5-28.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet, or into gear for a manual
transmission. When parking uphill, turn your wheels
away from the curb. When parking downhill, turn
your wheels into the curb.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
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Remote Oil Filter (Four-Wheel Drive)
The access door for the
remote oilfilter is in the
steering linkage shield
assembly located under
the radiator support.
Turn the screw to unlock
or lock the door. Make
sure if you open the door,
it is securely closed
when you arefinished.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Don’t let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
filter before disposal. Never dispose of oil by putting it in
the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by taking it
to a place that collects used oil. If you have a problem
properly disposing of your used oil, ask your dealer, a
service station or a local recycling center for help.
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How to Check and Add Fluid
The properfluid should be added if the level does not
reach the bottom of the diaphragm when it’s in place
in the reservoir. See the instructions on the
reservoir cap.
Engine Coolant
The cooling system in your vehicle isfilled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occursfirst, if you add
only DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating
on page 5-28.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F(−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as
they should.
Notice:When adding coolant, it is important that
you use only DEX-COOL
®(silicate-free) coolant.
If coolant other than DEX-COOL®is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner -- at 30,000 miles
(50,000 km) or 24 months, whichever occursrst.
Damage caused by the use of coolant other
than DEX-COOL
®is not covered by your new
vehicle warranty.
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What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t need to add anything else.
{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 the proper coolant.
Notice:If you use an improper coolant mixture, your
engine could overheat and be badly damaged. The
repair cost wouldn’t be covered by your warranty.
Too much water in the mixture can freeze and crack
the engine, radiator, heater core and other parts.If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don’t
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant recovery tank is located in the engine
compartment near the passenger side of the vehicle.
SeeEngine Compartment Overview on page 5-10
for more information on location.
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If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
•Tow a trailer. See“Driving on Grades”under
Towing a Trailer on page 4-51.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, idle the engine for three
minutes while you’re parked. Push down the accelerator
until the engine speed is about twice as fast as normal
idle speed for at least three minutes while you’re parked.
If you still have the warning,turn off the engine and get
everyone out of the vehicleuntil it cools down.
You may decide not to lift the hood but to get service
help right away.
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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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When the coolant in the coolant recovery tank is at the
ADD mark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper mixture
directly to the radiator, but be sure the cooling system
is cool before you do it.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap—even a little—they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
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Brake Wear
If you have four-wheel drive, your vehicle has four-wheel
disc brakes. If not, your vehicle has front disc brakes
and rear drum brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedalfirmly).
{CAUTION:
The brake wear warning sound means that
soon your brakes won’t work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes arefirst applied or lightly applied.
This does not mean something is wrong with your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specifications.
If you have rear drum brakes, they don’t have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately.
Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. When you have the front brake pads
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
SeeBrake System Inspection on page 6-32.Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If you don’t have four-wheel drive and your brake
pedal goes down farther than normal, your rear drum
brakes may need adjustment. Adjust them by backing
up andfirmly applying the brakes a few times.
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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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