1998 GMC ENVOY fuel

Loading Your Vehicle
The CertificatiodTire label is found on the driver’s door
edge, above the door latch. The label shows the size of
your original tires and the inflation pressures needed to
obtain the gross weight capacity
of your vehicle. This is
called the Gross Vehicle Weight Rating (GVWR). The
GVWR includes the weight of
the vehicle, all occupants,
fuel, cargo and trailer tongue weight, if pulling a trailer. The
Certification/Tire label
also tells you the maximum
weights for the front and rear axles, called
Gross Axle
Weight Rating (GAWR).
To find out the actual loads on
your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help
you with this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the GVWR for your vehicle,
or the
GAWR for either the
front or rear axle.
If you do have a heavy load, you should spread it out.
Similar appearing vehicles may have different GVWRs
and payloads. Please note your vehicle’s
Certificatian/Tire label or consult your dealer for
additional details.
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Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break,
or it can change the way your vehicle
handles. These could cause you to lose control. Also, overloading can shorten the life of
your vehicle.
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Every vehicle is ready for some trailer towing. If yours
was built with trailering options, as many are, it’s ready
for heavier trailers. But trailering is different than just
driving your vehicle by itself. Trailering means changes
in handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and
it has to be
used properly.
That’s
the reason for this part. In it are many
time-tested, important trailering tips and safety rules. Many
of these are important for your safety and that of
your passengers.
So please read this section carefully
before you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
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There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but
also where you’ll be driving.
A good source for this
information can be state or provincial police.
Consider using a sway control if your trailer
will
weigh 2,000 lbs. (900 kg) or less. You should always
use a sway control if your trailer will weigh more
than
2,000 Ibs. (900 kg). You can ask a hitch dealer
about sway controls.
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Don’t tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the first
500 miles (800 km) that you
tow a trailer, don’t drive over 50 mph (80 km/h) and
don’t make starts at full throttle. This helps your
engine and other parts of
your vehicle wear in at the
heavier loads.
You should use DRIVE
(D) (or, as you need to, a
lower gear) when towing a trailer. Operating your
vehicle
in DRIVE (D) when towing a trailer will
minimize heat buildup and extend the life
of
your transmission.
Three important considerations have to
do with weight:
the weight of the trailer,
0 the weight of the trailer tongue
0 and the weight on your vehicle’s tires.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the clutch is
not engaged. This improves fuel economy and
reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases when the clutch engages.
So you may hear an
increase in fan noise. This is normal and should not be
mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may
also hear this fan noise when you start the
engine. It will go away
as the fan clutch disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly.
If air goes
out of
a tire, it’s much more likely to leak out slowly.
But
if you should ever have a “blowout,” here are a few
tips about what to expect and what to do:
If
a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side.
Take your foot off the
accelerator pedal and grip
the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the
way you want the vehicle to go. It may be
very bumpy and noisy, but you can
still steer. Gently
brake to
a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to use your
iacking equipment to change
a flat tire safely. u Y a. c
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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.
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Service
Fuel
Fuels in Foreign Countries
Filling Your Tank
Filling a Portable
Fuel Container
Checking Things Under the Hood
Engine Oil
Air Cleaner
Automatic Transmission Fluid
Rear Axle
Four- Wheel Drive
Engine Coolant
Radiator Pressure Cap
Thermostat
Power Steering Fluid
Windshield Washer Fluid
Brakes Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Care of Safety Belts
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Service Parts Identification Label
Electrical System
Replacement Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
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You can be injured and your vehicle could be
damaged if you try to do service work on
a
vehicle without knowing enough about it.
0 Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
0 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.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around
it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use regular unleaded gasoline rated at 87 octane or
higher. At a minimum,
it should meet specifications
ASTM D48 14
in the United States and CGSB 3.5-M93
in Canada. Improved gasoline specifications have been
developed by the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting the AAMA
specification could provide improved driveability and
emission control system protection compared
to
other gasolines.
Be SUI-e 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
hear heavy knocking, your engine needs service. But
don‘t worry
if you hear a little pinging noise when
you’re accelerating or driving
LIP 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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If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications. If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily
on fuels meeting
federal specifications,
but emission control system
performance may be affected. The malfunction indicator
lamp
on your instrument panel may turn on and/or your
vehicle may fail a smog-check test.
If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause of failure. In the event it is determined that the
cause of the condition is
the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are
not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does
not recommend the
use of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator lamp on your instrument panel
may turn
on. If this occurs, return to your authorized
GM dealer for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming
in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should not have to add
anything to
the fuel. In addition, gasolines containing
oxygenates, such as ethers and ethanol, and
reformulated gasolines may be available in your area
to
help clean the air. General Motors recommends that you
use these gasolines
if they comply with the
specifications described earlier.
I NOTICE:
Your vehicle was not designed for fuel that
contains methanol. 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.
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Fuels in Foreign Countries
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
Filling Your Tank
The fuel cap is behind a hinged door on the driver’s side
of your vehicle.
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Gasoline vapor is highly flammable. It burns
violently, and that can cause very bad injuries.
Don’t smoke if you’re near gasoline or refueling
your vehicle. Keep sparks, flames and smoking
materials away from gasoline.
While refueling, hang the cap by the tether from the
hook on the filler door.
To remove the cap, turn it slowly to the left
(counterclockwise). The cap has a
spring in it; if you let
go of the cap too
soon, it will spring back to the right.
A CAUTION:
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If you get gasoline on yourself and then
something ignites it, you could be badly burned.
Gasoline can spray out on you
if you open the
fuel filler cap too quickly. This spray can happen
if your tank
is nearly full, and is more likely in
hot weather. Open the fuel filler cap slowly and
wait for any “hiss” noise
to stop. Then unscrew
the cap all the way.
Be careful not to spill gasoline. Clean gasoline from
painted surfaces as soon as possible. See “Cleaning the
Outside
of Your Vehicle” in the Index.
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