1995 CHEVROLET TAHOE service

Downloaded from www.Manualslib.com manuals search engine 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 ofthe 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.
Cooling System - Gasoline Engines
When you decide it’s safe to lift the hood, here’s what you’ll see:
A. Coolant recovery tank
B . Engine fan( s)
C. Radiator pressure cap
If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until
it cools down.
5-1 1

Downloaded from www.Manualslib.com manuals search engine 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.
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 50/50 mixture of clean 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.)

Downloaded from www.Manualslib.com manuals search engine 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
NOTICE:
The diesel engine has a specific coolant fill procedure. Failur\
e 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 clean 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.)
5-19

Downloaded from www.Manualslib.com manuals search engine Service & Appearance Care
Section
Here you will find information about the care of your vehicle. This section 1
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.
f
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:
a-?:
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.
6-1

Downloaded from www.Manualslib.com manuals search engine You should keep a record with all parts receipts and list the mileage and the
date
of any servi-work you perform. See “Maintenance Record” in the
Index.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains the
maintenance your
new vehicle needs, and when it should be done. It also
has a form that
you can use to record the maintenance work done on your
vehicle. Be sure
to read this information.
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.
6-2

Downloaded from www.Manualslib.com manuals search engine 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.
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.
Methnrzol 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.
6-3

Downloaded from www.Manualslib.com manuals search engine 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:
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 conditions) 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 -1 8°C); however, it will produce
a power and fuel economy
loss. The use of Number 1-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.
6-4

Downloaded from www.Manualslib.com manuals search engine 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 cold 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 fills below 0°F (-I 8”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
I 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 (0°C 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.