1995 GMC SIERRA service

If No Steam Is Coming From Your Engine
If you get the 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:
0 Climb a long hill on a hot day.
0 Stop after high speed driving.
0 Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades’’ in the Index.
If
you get the overheat warning with no sign of steam, try this for a minute
or
so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan speed and open the
window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N); otherwise, shift to the
highest gear while driving
- AUTOMATIC OVERDRIVE (@) or
DRIVE
(3) for automatic transmissions.
If you no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten 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, push the accelerator until the engine speed is
about twice as fast as normal idle speed. Bring the engine speed back to
normal idle speed after two or three minutes. Now see
if the warning stops.
But then, if
you still have the warning, turn ofSthe engine and get everyone
out of the vehicle until it cools down.
You may decide not to lift the hood but to get service help right away.
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The coolant level
should be a1 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.
A CAUTION:
Heater and radiator hoses, and other engine parts, can be very
hot. Don’t touch them.
If you do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, it
could lose all coolant. That could cause an engine fire, and you
could be burned. Get any leak fixed before you drive the vehicle.
NOTICE:
Engine damage from running your engine without coolant isn’t
covered
by your warranty.
If there seem 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.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the COLD mark, add
a SO/SO mixture of c.lea12 water (preferably distilled)
and
a proper antifreeze at the coolant recovery tank. (See “Engine Coolant”
in the Index for more information about the proper coolant mix.)
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I A CAUTION:
Heater and radiator hoses, and other engine parts, can be very
hot. Don’t touch them.
If you do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, it
could lose all coolant. That could cause an engine
fire, and you
could be burned. Get any leak fixed before you drive the vehicle.
I 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.
How to Add Coolant to the Coolant Surge Tank
I NOTICE:
The diesel engine has a specific coolant fill procedure. Failure to
follow this procedure could cause your engine to overheat and be
severely damaged.
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark, add a
50/50 mixture of cleun water (preferably distilled) and a proper
antifreeze at the coolant surge tank, but be sure the cooling system,
including the
coolant surge tank pressure cap, is cool before you do it. (See
“Engine Coolant”
in the Index for more information about the proper
coolant mix.)
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Service & Appearance Care
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 part devoted to its appearance care.
Service
Your GM 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 get the
proper
GM Service Manual. It tells you much more about how to service
your vehicle than this manual can.
To order the proper service manual, see
“Service Publications”
in the Index.
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You should keep a record with all parts receipts and list the mileage and the
date
of any service work you perform. See “Maintenance Record” in the
Index.
A CAUTION:
You can be injured if you try to do service work on a vehicle
without knowing enough about it,
Be sure you have sufficient knowledge, experience, and the
proper replacement parts and tools before you attempt
any
vehicle maintenance task.
Be sure to use the proper nuts, bolts and other fasteners,
“English” and “metric” fasteners can be easily confused. If
you use the wrong fasteners, parts can later break or fall
off.
You could be hurt.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel Requirements and Fuel
System”
in this Section. For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at 87 octane or higher. It should meet
specifications ASTM D48
14 in the United States and CGSB 3.5-92 in
Canada. These fuels should have the proper additives, so you should not
have to add anything
to the fuel.
In the United States and Canada, it’s easy to be sure
you get the right kind
of gasoline (unleaded). You’ll see UNLEADED right on the pump. And
only unleaded nozzles will
fit into your vehicle’s filler neck.
Be sure the posted octane is at least
87. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If it’s bad enough,
it can
damage your engine.
If you’re using fuel rated at 87 octane or higher and you still hear heavy
knocking, your engine needs service. But don’t worry
if you hear a little
pinging noise when you’re accelerating or driving up a hill. That’s normal
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the
heavy, constant knock that means you have a problem.
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What about gasoline with blending materials that contain oxygen
(oxygenates), such
as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.” Fuel that is no more than 15%
MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel that is no more than
10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
NOTICE:
Fuel that is more than 5% methanol is bad for your vehicle.
Don’t use it. It can corrode metal parts in your fuel system and
also damage plastic and rubber parts. That damage wouldn’t be
covered under your warranty. And even at
5% or less, there
must be “cosolvents” and corrosion preventers in this fuel
to
help avoid these problems.
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 Sysrem
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.
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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:
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.
What Fuel to Use
For best results, use Number 2-D diesel fuel year-round (above and below
freezing conditionsj as oil companies blend Number
2-D fuel to address
climate differences. Number
1-D diesel fuel may be used in very cold
temperatures (when
it stays below 0°F or -18°C); however, it will produce
a power and fuel economy loss. The use of Number I-D diesel fuel in warm
or hot climates may result in stalling, poor starting when the engine is hot
and
may damage the fuel injection system.
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.
A CAUTION:
Heat coming from the engine may cause the fuel to expand and \
force the fuel out of your tank.
If something ignites the fuel, a
fire could start and people could be burned. To help avoid this,
fill your fuel tank only until the automatic nozzle shuts
off.
Don’t try to “top it off.”
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect
the function of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use.”
If you’re driving
in very toold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-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 S”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 (waxed). To unclog it,
warm the filter to between
32°F and 50°F (OOC to 10°C). You won’t need
to replace
it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen
if a service station doesn’t regularly inspect and clean
its fuel tanks, or
if it gets contaminated fuel from its suppliers.
If this happens, a WATER
IN FUEL light will come on. If it does, the excess
water must be drained. Your dealer can show
you how to do this.
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