tires GMC ENVOY 1998 Owner's Manual

Driving with a Trailer
A CAUTION: I
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If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can’t see
or smell
CO. It can cause unconsciousness or
death. (See ‘(Engine Exhaust” in the Index.) To
maximize your safety when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle.
Do not use
RECIRCULATION because it only
recirculates the air inside your vehicle. (See
“Comfort Controls” in the Index.)
Towing a trailer requires a certain amount of experience, ~
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
arc
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you
start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to
be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you 1
would when driving your vehicle without a trailer. This
can help you avoid situations that require heavy braking
and sudden turns.
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Towing Your Vehicle
Try to have a GM dealer or a proressional towing
service tow your vehicle. See "Roadside Assistance"
in
the Index.
If your vehicle has been changed since it was
factory-new by adding things like fog lamps, aero
skirting, or special tires and wheels, these instructions
may not be correct.
Before you do anything, turn
on the hazard
warning flashers.
When you call,
tell the towing service:
0 That your vehicle has four-wheel drive.
0 The make, model and year of your vehicle.
0 Whether you can rnolle the shift lever for the
transmission and shift the transfer case.
0 If there was an accident, what was damaged.
When the towing service arrives,
let the tow operator
know that this manual contains these towing
instructions. The operator may want to see them.
To help avoid injury to you or others:
0 Never let passengers ride in a vehicle that is
Never tow faster than safe or posted speeds.
Never tow with damaged parts not
Never get under your vehicle after it has
Always use separate safety chains on each
0 Never use J-hooks. Use T-hooks instead.
being
towed.
fully secured.
been lifted by the tow truck.
side when towing
a vehicle.
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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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If You’re Stuck: In Sand, Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help
you get out when you’re stuck, but
you must use caution.
A CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts
of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
I
NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
For information about using tire chains on your vehicle,
see “Tire Chains”
in the Index.
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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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Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque
wheel nuts in the
proper sequence to
GM specifications.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection” in Section
7 of this manual
under Part
C “Periodic Maintenance Inspections.”
Brakc Jedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a modern vehicle is complex.
Its many parts have to be
of top quality and work well
together
if the vehicle is to have really good braking.
Your vehicle was designed and tested with top-quality
GM brake parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and
you have to have new ones put in -- be sure
you get new approved GM replacement parts.
If you
don’t, your brakes may
no longer work properly. For
example,
if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you’ve come to expect can change in many
other ways if someone puts
in the wrong replacement
brake parts.
Battery
Every new vehicle has an ACDelco Freedom@ battery.
You never have to add water to one of these. When it’s
time for a new battery, we recommend an ACDelco
Freedom battery. Get one that has the replacement
number shown on the original battery’s label.
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5. Be sure that the notches are locked by the bottom
claws. Make sure that all other claws are properly
locked on both sides
of the insert slots.
A
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A. Claw in Notch
B. Correct Installation
C. Incorrect Installation
6. Put the blade assembly pivot in the wiper arm
hook. Pull up until the pivot locking tab locks in
the hook
slot.
7. Carefully lower the wiper arm and blade assembly
onto the windshield.
Backglass Wiper Blade Rep --ment
See “Windshield Wiper Blade Replacement” in this
section
for instructions on how to change the backglass
wiper blade. The backglass wiper blade will not lock
in a vertical position like the windshield wiper blade,
so care should be used when pulling it away from
the vehicle.
Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service, see
your
GMC Warranty booklet for details.
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Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as
a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index.
Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be cut,
punctured or broken by a sudden impact
--
such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The CertificatiodTire label, which is on the driver’s
door edge, above the door latch, shows the correct
inflation pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than
1 mile (1.6 km).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not.
If your tires
don’t have enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
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NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the
tire pressure
of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t
tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
( 10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires
as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later in
this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
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Q
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When rotating your tires, always use one of the correct
rotation. patterns shown here.
After the tires
have been rotated, adjust the front and rear
inflation pressures as shown on the Certificationflire
label.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque”
in the Index.
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after
a time. The wheel could come off and cause
an accident. When
you change a wheel, remove
any rust or dirt from places where the wheel
attaches
to the vehicle. In an emergency, you can
use a cloth or
a paper towel to do this; but be
sure to use a scraper or wire brush later,
if you
need to, to get all the rust or dirt off. (See
“Changing a Flat Tire”
in the Index.)
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