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2-22
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
Automatic Transmission Operation
There are several
different positions
for your shift lever.PARK (P): This position locks your wheels. It's the best
position to use when you start your engine because your
vehicle can't move easily.
CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
Don't leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle won't move, even when you're on fairly
level ground, always set your parking brake and
move the shift lever to PARK (P).
See ªShifting Into PARK (P)º in the Index.
If you're pulling a trailer, see ªTowing a Trailerº
in the Index.
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2-75 Oil Pressure Gage
The oil pressure gage shows
the engine oil pressure in
psi (pounds per square inch)
when the engine is running.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or other problems causing low
oil pressure.CAUTION:
Don't keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
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2-77 Check Gages Light
The CHECK GAGES light
will come on briefly when
you are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil pressure
gages to see if they are in the warning zones.
Gate Ajar Light
If this light comes on, your
liftgate or liftglass is ajar.
Try closing the liftgate or
liftglass again. Never drive
with the liftgate or liftglass
even partially open.
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6-13
As in the chart shown previously, SAE 5W-30 is best for
your vehicle. However, you can use SAE 10W
-30 if it's
going to be 0F (
-18C) or above. These numbers
on an oil container show its viscosity, or thickness.
Do not use other viscosity oils, such as SAE 20W
-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
starburst symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench oil meets all the requirements
for your vehicle.
If you are in an area where the temperature falls below
-20F (-29C), consider using either an SAE 5W-30
synthetic oil or an SAE 0W
-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
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 to 10 miles (8 to 16 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 operate your vehicle in dusty areas or
off
-road frequently.
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 and filter
every 3,000 miles (5 000 km) or 3 months
-- whichever
occurs first.
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6-16
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter 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 90F (32C) 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 the fluid and filter
every 50,000 miles (83 000 km).
See ªScheduled Maintenance Servicesº in the Index.
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 little fluid can damage your
transmission. Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be sure to get an accurate reading if you check
your transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90F (32C).
At high speed for quite a while.
In heavy traffic
-- especially in hot weather.
While pulling a trailer.
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6-21
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 ªScheduled Maintenance Servicesº in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you'll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See ªRecommended Fluids and
Lubricantsº in the Index.
Engine Coolant
The cooling system in your vehicle is filled 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 occurs first, 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, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:
Give freezing protection down to
-34F (-37C).
Give boiling protection up to 265F (129C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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Scheduled Maintenance
7-5
Short Trip/City Definition
Follow the Short Trip/City Scheduled Maintenance if
any one of these conditions is true for your vehicle:
Most trips are less than 5 to 10 miles (8 to 16 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 operate your vehicle in dusty areas or
off
-road frequently.
You frequently tow a trailer or use a carrier on top
of your vehicle.
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 (or 3 months, whichever
occurs first).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air
Cleaner Filter Inspection, if driving in dusty
conditions. 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).
Transfer Case Fluid Change.
(Continued)
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Short Trip/City Scheduled Maintenance
7-11
15,000 Miles (25 000 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 #.)
Inspect engine air cleaner filter if you are driving in dusty conditions.
Replace filter if necessary.
An Emission Control Service. (See footnote .)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
Change automatic transmission fluid and filter if the vehicle is mainly driven
under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly reaches
90F (32C) 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 the
fluid and filter every 50,000 miles (83 000 km).ACTUAL
SERVICED BY:MILEAGE
DATE
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