fuel GMC ENVOY 2001 Owner's Manual

4-35
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted.
Reduce your speed according to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds, you may tend to think you are going
slower than you actually are.
Before Leaving on a Long Trip
Make sure you're ready. Try to be well rested. If you
must start when you're not fresh
-- such as after a day's
work
-- don't plan to make too many miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it's ready to go. If it needs
service, have it done before starting out. Of course,
you'll find experienced and able service experts in
GM dealerships all across North America. They'll be
ready and willing to help if you need it.Here are some things you can check before a trip:

Windshield Washer Fluid: Is the reservoir full?
Are all windows clean inside and outside?

Wiper Blades: Are they in good shape?

Fuel, Engine Oil, Other Fluids: Have you checked
all levels?

Lamps: Are they all working? Are the lenses clean?

Tires: They are vitally important to a safe,
trouble
-free trip. Is the tread good enough for
long
-distance driving? Are the tires all inflated to
the recommended pressure?

Weather Forecasts: What's the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?

Maps: Do you have up
-to-date maps?
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4-41
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will
help keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
Recreational Vehicle Towing
There may be times when you want to tow your vehicle
behind another vehicle for use at your destination.
Be sure to use the proper towing equipment designed
for recreational vehicle towing. Follow the instructions
for the towing equipment.
When towing your vehicle, turn the ignition to OFF.
To prevent your battery from draining while towing,
remove the RDO BATT and CLSTR fuses from the
instrument panel fuse block. Be sure to replace the fuses
when you reach your destination. See ªFuses and Circuit
Breakersº in the Index.
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4-43
4. With the engine running, shift the transfer case to
NEUTRAL. See ªFour
-Wheel Driveº in the Index
for the proper procedure to select the NEUTRAL
position for your vehicle.
CAUTION:
Shifting the transfer case into NEUTRAL can
cause your vehicle to roll even if the transmission
is in PARK (P), for an automatic transmission,
or if your vehicle is in gear, for a manual
transmission. You or others could be injured.
Make sure the parking brake is firmly set
before you shift the transfer case into NEUTRAL.
See ªFour
-Wheel Drive (Automatic Transfer Case)º
in the Index.
5. Release the parking brake only after the vehicle
being towed is firmly attached to the towing vehicle.
6. Turn the ignition to OFF. The OFF position unlocks
the steering column and reduces battery drain.
Unlocking the steering column will allow the proper
movement of the front wheels and tires during towing.
Loading Your Vehicle
The Certification/Tire 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).
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4-47
NOTICE:
Pulling a trailer improperly can damage your
vehicle and result in costly repairs not covered
by your warranty. To pull a trailer correctly,
follow the advice in this part, and see your
dealer for important information about towing
a trailer with your vehicle. Additional rear axle
maintenance is required for a vehicle used to tow
a trailer. See ªScheduled Maintenance Servicesº
in the Index.
To identify what the vehicle trailering capacity is for
your vehicle, you should read the information in
ªWeight of the Trailerº that appears later in
this section.
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.
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4-49
Tow/Haul Mode (V6 Engine, Automatic
Transmission Equipped Models) (If Equipped)
The tow/haul mode is a feature that assists when pulling
a heavy trailer. The purpose of the tow/haul mode is to
do the following:

Reduce the frequency of shifts when pulling a
heavy trailer,

provide the same shift feel when pulling a heavy
trailer as when the vehicle is unloaded, and

reduce the need to change throttle position when
pulling a heavy trailer.
This feature is turned on or off by pressing a button
on the floor console or the shift knob. When the feature
is on, a light located on the instrument panel cluster
will illuminate to indicate that the tow/haul mode has
been selected.
See ªTow/haul Mode Lightº in the Index. The tow/haul
mode is automatically turned off each time the vehicle
is started.The tow/haul mode is most effective when the vehicle
and trailer combined weight is at least 75% of the Gross
Vehicle Weight Rating (GVWR) and the maximum
trailer weight rating for the vehicle. See ªGross Vehicle
Weight Ratingº and ªTrailer Weightº in the Index.
The tow/haul mode for hauling a heavy trailer is most
useful under the following conditions:

When driving through hilly terrain at speeds
below 55 mph (88 km/h),

when driving in low speed or stop and go traffic
below 55 mph (88 km/h), and

when driving in parking lots.
Use the tow/haul mode instead of the previous
recommendation to shift to THIRD (3) gear to improve
fuel economy at highway speeds and shift performance
at lower speeds. Operating in the tow/haul mode when
not pulling a heavy trailer will not cause damage to the
vehicle, but you may experience reduced fuel economy
and undesirable performance from the engine and
transmission. The tow/haul mode should be used
only when pulling a heavy trailer.
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5-17
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 ªblow outº 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 ªblowout,º 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
jacking equipment to change a flat tire safely.
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6-
6-1
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.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-6 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-11 Engine Oil
6
-16 Engine Air Cleaner/Filter
6
-17 Automatic Transmission Fluid
6
-20 Manual Transmission Fluid
6
-21 Hydraulic Clutch
6
-22 Rear Axle
6
-22 Four-Wheel Drive
6
-24 Engine Coolant
6
-27 Radiator Pressure Cap
6
-28 Power Steering Fluid
6
-28 Windshield Washer Fluid6
-30 Brakes
6
-34 Battery
6
-35 Bulb Replacement
6
-42 Windshield Wiper Blade Replacement
6
-44 Tires
6
-53 Appearance Care
6
-53 Cleaning the Inside of Your Vehicle
6
-56 Care of Safety Belts
6
-57 Cleaning the Outside of Your Vehicle
6
-61 GM Vehicle Care/Appearance Materials
6
-62 Vehicle Identification Number (VIN)
6
-62 Service Parts Identification Label
6
-63 Electrical System
6
-72 Replacement Bulbs
6
-72 Capacities and Specifications
6
-73 Normal Maintenance Replacement Parts
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6-3
CAUTION:
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.

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.

Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
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. It is recommended that the gasoline meet
specifications which were developed by the American
Automobile Manufacturers Association (AAMA) and
endorsed by the Canadian Motor Vehicle Manufacturers
Association for better vehicle performance and engine
protection. Gasolines meeting the AAMA specification
could provide improved driveability and emission control
system performance compared to other gasolines.
In Canada, look for the
ªAuto Makers' Choiceº
label on the fuel pump.
Canada Only
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6-4
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 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.
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. See ªMalfunction Indicator Lampº
in the Index. 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 may contain an octane
-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask your service station operator
whether or not the 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.
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6-5
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 contribute to clean air. General Motors
recommends that you use these gasolines, particularly
if they comply with the specifications described earlier.
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.
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.
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