1998 GMC ENVOY tires

What’s the worst time for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive on.
But wet
ice can be even more trouble because
it may offer the
least traction
of all. You can get wet ice when it’s about
freezing
(32°F; OOC) and freezing rain begins to fall.
Try to avoid driving on wet ice
until salt and sand crews
can get there. Whatever
the condition
-- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently. Try not to break the fragile traction.
If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when you make
a hard stop on a slippery road. Even
though
you have an anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock”
in the Index.
Allow greater following distance on any
slippery road.
Wdtch for slippery spots. The road might be fine
until you hit a spot that’s covered with ice. On an
otherwise clear road, ice patches may appear
in
shaded areas where the sun can’t reach: around
clumps
of trees, behind buildings or under bridges.
Sometimes the surface
of a curve or an overpass may
remain icy when
the surrounding roads are clear. If
you see a patch of ice ahead of you, brake before you
are on
it. Try not to brake while you’re actually on
the ice, and avoid sudden steering maneuvers.
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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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A B
If you’re using a weight-carrying hitch, the trailer
tongue (A) should weigh
10 percent of the total loaded
trailer weight
(B). If you’re using a weight-distributing
hitch, the trailer tongue
(A) should weigh 12 percent of
the total loaded trailer weight (B).
After you’ve loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights are
proper. If they aren’t,
you may be able to get them right
simply by moving some items around in the trailer.
1 Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the upper
limit for cold tires. You’ll find these numbers on the
CertificatiodTire label on the driver’s door edge, above
the door latch, or see “Tire Loading”
in the Index. Then
be sure
you don’t go over the GVW limit for your
vehicle, including the weight
of the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are a
few reasons why you’ll need the right hitch. Here are
some rules to follow:
0 If you’ll be pulling a trailer that, when loaded, will
weigh more than
3,500 lbs. (1 589 kg), be sure to use
a properly mounted, weight-distributing hitch and
sway control of the proper size. This equipment is
very important for proper vehicle loading and good
handling when you’re driving.
0 Will you have to make any holes in the body of your
vehicle when you install
a trailer hitch?
If you do, then be sure to seal the holes later when
you remove the hitch. If you don’t seal them, deadly
carbon monoxide (CO) from your exhaust can get
into your vehicle (see “Carbon Monoxide” in the
Index). Dirt and water can, too.
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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.
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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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