1995 GMC SIERRA fuel additives

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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