1999 GMC C-SERIES check oil

6-
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-4 Fuel (Gasoline Engine)
6
-5 Diesel Fuel Requirements and Fuel System
6
-6 Fuels in Foreign Countries (Gasoline Engines)
6
-7 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-9 Checking Things Under the Hood
6
-11 Noise Control System
6
-13 Engine Oil (Gasoline Engine)
6
-17 Engine Oil (Caterpillar
Diesel Engine)
6
-17 Engine Air Cleaner/Filter
6
-18 Automatic Transmission Fluid
6
-19 Manual Transmission Fluid
6
-20 Rear Axle
6
-20 Rear Axle Shift Motor (Option)
6
-21 Radiator Pressure Cap (Gasoline Engines)
6
-22 Surge Tank Pressure Cap (Diesel Engines)
6
-22 Thermostat6
-23 Engine Coolant (Gasoline Engine)
6
-27 Engine Coolant (Caterpillar
Diesel Engine)
6
-28 Power Steering Fluid
6
-29 Windshield Washer Fluid
6
-30 Brakes
6
-36 Electric/Hydraulic Parking Brake Fluid
6
-42 Battery
6
-44 Other Service Items
6
-48 Tires
6
-59 Appearance Care
6
-59 Cleaning the Inside of Your Vehicle
6
-63 Cleaning the Outside Your Vehicle
6
-66 GM Vehicle Care/Appearance Materials
6
-67 Vehicle Identification Number (VIN)
6
-67 Service Parts Identification Label
6
-68 Electrical System
6
-74 Capacities and Specifications
6
-77 Air Conditioning Refrigerants
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6-6
NOTICE:
If there is water in your diesel fuel and the
weather is warm or humid, fungus and bacteria
can grow in the fuel. They can damage your fuel
system. You'll need a diesel fuel biocide to
sterilize your fuel system. Your dealer can advise
you if you ever need this.
If your fuel tank needs to be purged to remove
water, see your dealer or a qualified technician.
Improper purging can damage your fuel system.
Diesel engine vehicles that stand unused for several
days or weeks can develop water in the fuel from
condensation. It helps to fill the fuel tank if the
diesel engine vehicle will not be used for a time.
Fuels in Foreign Countries
(Gasoline Engines)
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard to
find. Never use leaded gasoline or any other fuel not
recommended in the previous text on fuel. Costly repairs
caused by use of improper fuel wouldn't be covered by
your warranty.
To check on fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you'll be driving.
You can also write us at the following address for
advice. Just tell us where you're going and give your
Vehicle Identification Number (VIN).
General Motors Overseas Distribution Corporation
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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6-13
Engine Oil (Gasoline Engine)
It's a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
The engine oil dipstick is located on the passenger's side
of the engine compartment.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don't, the oil dipstick
might not show the actual level.
Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
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6-18
CAUTION:
Gasoline Engines Only: Operating the engine
with the air cleaner/filter off can cause you or
others to be burned. The air cleaner not only
cleans the air, it stops flame if the engine
backfires. If it isn't there, and the engine
backfires, you could be burned. Don't drive with
it off, and be careful working on the engine with
the air cleaner/filter off.
NOTICE:
Gasoline Engines Only: If the air cleaner/filter is
off, a backfire can cause a damaging engine fire.
And, dirt can easily get into your engine, which
will damage it. Always have the air cleaner/filter
in place when you're driving.
Your vehicle may also be equipped with an optional
Filterminder gage. See ªWarning Lights, Gages and
Indicatorsº in the Index.
Automatic Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
checked. See your Allison Automatic Transmission
Operator's Manual to find out when to change your
transmission fluid and filters.
How to Check and What to Use
The Allison Automatic Transmission Operator's Manual
that came with the vehicle shows how to check the
automatic transmission fluid and what fluid to use.
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.
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6-19 Automatic Transmission External Filter
Your automatic transmission spin-on type filter requires
periodic replacement. It is mounted just behind the
radiator on the outside of the passenger's side frame rail.
Consult the Allison Automatic Transmission Operator's
Manual that came with the vehicle for proper
change intervals.
Automatic Transmission External Filter
With Service Trans Filter Indicator Light
(Option)
This automatic transmission spin-on type filter is
mounted to the left of the transmission. It requires
replacement when the SERVICE TRANS FILTER
indicator light on the instrument panel comes on or
every three years, whichever occurs first.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
checked. See your Maintenance Schedule to find out
when to change your transmission fluid and filters.
How to Check and What to Use
The Eaton Fuller Transmission Operator's Manual that
came with the vehicle shows how to check the manual
tranmsmission fluid and what fluid to use.
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.
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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 ªScheduled Maintenance Servicesº in the
Maintenance Schedule.
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 Maintenance Schedule.
Rear Axle Shift Motor (Option)
When to Check and Change Fluid
If you have an optional air-shift two-speed, controlled
traction, or locking differential type rear axle, a good
time to check the fluid level in the axle shift motor is
when the rear axle lubricant is checked. Use refrigerant
oil (shift motor only).
How to Check Fluid
Remove the plug on the front plate of the axle shift
motor, add enough fluid to raise the level to the bottom
of the filler plug hole, then replace the plug.
What to Use
Refer to your Maintenance Schedule to determine what
kind of lubricant to use.
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6-24 What to Use
Use a mixture of one-half clean, drinkable water and
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 like 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
catch fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable water
and DEX
-COOL
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.
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6-45 Fuel Filter (Diesel Engines)
The ACDelco
fuel filter is located in the component
box. See your Maintenance Schedule for recommended
service intervals.
Primary Fuel Filter and Water Separator
(Option)
If you have a Caterpillar

diesel engine, you may
have this spin
-on filter.
It is in the component box
on the driver's side behind
the fender.
It has a clear plastic drain bowl at the bottom. Check the
drain bowl occasionally for any water or particles. To
drain the bowl, shut off the engine. Then partially open
the drain valve at the bottom of the filter. See ªEngine
Oilº in the Index for proper disposal procedures.
Secondary Fuel Filter and Water
Separator/Heater (Option)
If you have a Caterpillar

diesel engine, you may have
this spin
-on filter and fuel
separator/heater. It is
mounted on the passenger's
side of the engine.
It has a metal drain bowl at the bottom. Occasionally, check
the bowl for any water or particles. To check or drain the
bowl, shut off the engine. Then push up on the spring loaded
drain valve until clear fuel is flowing from the valve. The
particles or water will drain out first. See ªEngine Oilº in the
Index for proper disposal procedures.
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