1994 CHEVROLET SUBURBAN engine oil

Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important in trailer operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, and brake
adjustment. Each
of these is covered in this manual, and the Index will help
you find them quickly. If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see
that all hitch nuts and bolts are tight.
Trailer Light Wiring
See “Trailer Wiring Harness” in the Index.
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If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until it cools down.
P
The coolant level
should be at or above
the
COLD mark. If it
isn’t,
you may have a
leak in the radiator
hoses, heater hoses,
radiator, water
pump
or somewhere else in
the cooling system.
NOTICE:
Engine damage from running your engine without coolant isn’t \
covered
by your warranty.
If there seems to be no leak, start the engine again. See if the fan speed
increases
when idle speed is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off the engine.
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If the coolant inside the coolant surge tank is boiling, don't do anything else
until it cools down.
The coolant level
should be at
or above
the
COLD mark. If it
isn't, you may have
a
leak in the radiator
hoses, heater hoses,
radiator, water
pump
or somewhere else in
the cooling system.
NOTICE:
Engine damage from running your engine without coolant isn't
covered by your warranty.
If there seems to be no leak, start the engifie again. See if the fan speed
increases when idle speed
is doubled by pushing the accelerator pedal down
If
it doesn't, your vehicle needs service. Turn off the engine.
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Service & Appearance
I Section
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 section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
............................
Diesel Fuel Requirements and Fuel System ..........
Checking Things Under the Hood ........... .....
........ 6-4
.......... 6-5
......... 6-14
HoodRelease
.......................................... 6-14
Cleaning Your Diesel Engine
............................ 6-15
Engine Oil (Except Diesel)
................................ 6-16
Engine Oil (Diesel Engines)
............................... 6-22
Aircleaner
.................... .................. 6-27 ..
Automatic Transmission Fluid ............................. 6-28
Manual Transmission Fluid
............................... 6-31
Hydraulic Clutch
........................................ 6-32
RearAxle
............................................. 6-33
Transfer Case
.......................................... 6-34
FrontAxle
........................................... 6-35
Engine Coolant
......................................... 6-35
Power Steering Fluid
.............. .................. 640
Windshield Washer Fluid
............................... 6-42
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Gasolines for Cleaner Air
Your use of gasoline with deposit control additives will help prevent
deposits from forming
in your engine and fuel system. That helps keep your
engine in tune and your emission control system working properly. It’s good
for your vehicle, and you’ll be doing your part for cleaner air.
Many gasolines are now blended with oxygenates. General Motors
recommends that you use gasolines with these blending materials, such as
MTBE and ethanol. By doing
so, you can help clean the air, especially in
those parts of the country that have high carbon monoxide levels.
In addition, some gasoline suppliers are now producing reformulated
gasolines. These gasolines are specially designed to reduce vehicle
emissions. General Motors recommends that you use reformulated gasoline.
By doing
so, you can help clean the air, especially in those parts of the
country that have high ozone levels.
You should ask your service station operators if their gasolines contain
deposit control additives and oxygenates, and
if they have been
reformulated to reduce vehicle emissions.
Diesel Fuel Requirements and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you to
buy permits or pay special taxes.
Some of these restrictions apply only to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions
in any state or province, contact your auto club, the police or
other officials.
Fuel Requirements
NOTICE:
Diesel fuel or fuel additives not recommended in this manual
could damage your fuel system and engine, Your warranty
wouldn’t cover this damage, And:
0 Diesel fuel that has been mixed with engine oil could damage
your engine and emission controls. Always check with your
service station operator to make sure his diesel fuel has not
been mixed with engine oil.
If you ever run out of diesel fuel, it can be difficult to restart
your engine. “Running Out of Fuel,” later in this section,
tells
you how to get it started again. To avoid all this, try never to
let your tank get empty.
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What Fuel to Use
You can use either Number 1-D or Number 2-D diesel fuel, but you’ll get
better fuel economy using
2-D.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle to shut
off, even though your tank isn’t full. If this happens,
just wait
for the foaming to stop and then continue to fill your tank.
Cold Weather Operation
In cold weather (below 20”F, or -7”C), use 1-D or “Winterized” Number
2-D fuel (a blend of 1-D and 2-D). Be sure you get the right fuel. In very
cold temperatures (when it stays below
0°F or -18”C), use Number 1-D.
If you’re driving in very cold temperatures and can’t get Number 1-D or a
“winterized” Number
2-D, you can use one gallon of kerosene for every
two gallons of diesel fuel. Once you add the kerosene, run your engine for
several minutes
so the fuels will mix. Add kerosene only when the
temperature falls below
0°F (-1 8 “C), because the fuel economy of kerosene
isn’t as good
as that of diesel fuel.
NOTICE:
Never use home heating oil or gasoline in your diesel engine.
They can cause engine damage.
In cold weather, your fuel filter may become clogged, especially if you use
Number 2-D diesel fuel that hasn’t been “winterized.” To unclog it, warm
the filter to between
32°F and 50°F (0°C to 10°C). You won’t need to
replace it.
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To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
2. Remove the fuel tank cap.
the parking brake.
3. Place a
fuel-resistant container under the filter
drain hose.
4. With the engine
off, open the
water drain valve
2 to 3 turns.
When standing in
front of the
vehicle,
the valve
is located
on the
right side
of the
thermostat housing.
5. Start the engine and allow it to idle until clear fuel is observed.
6. Stop the engine and close the water drain valve.
7. Remove the fuel-resistant container and properly dispose of the
contaminated fuel. To find out how
to properly dispose of contaminated
diesel
fuel see “What to Do with Used Oil” in the “Engine Oil (Diesel
Engines)” part, later in
this section.
8. Install the fuel tank cap.
If the
WATER IN FUEL light comes on again after driving a short distance
or the engine
runs rough or stalls-a large amount of water has probably
been pumped into the fuel tank. The fuel tank should be purged.
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Fuels in Foreign Countries
If you plan on driving in another country outside the U.S. or Canada,
unleaded fuel may be hard to find.
Do not use leaded gasoline. If you use
even one tankful, your emission controls won’t work well or at all. With
continuous use, spark plugs can get fouled, the exhaust system can corrode,
and your engine oil can deteriorate
quickly. Your vehicle’s oxygen sensor
will be damaged. All of that means costly repairs that 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,
North American Export Sales
(NAES)
1908 Colonel Sam Drive
Oshawa, Ontario
LlH 8P7
Filling Your Tank
The fuel cap is behind
a hinged door on the
left side of your
vehicle.
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