2004 GMC ENVOY XL tires

Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on page 4-16
for information about driving off-road.
Keep your vehicle in good shape. Check all uid
levels and also the brakes, tires, cooling system and
transmission. These parts can work hard on
mountain roads.
Know how to go down hills. The most important thing
to know is this: let your engine do some of the
slowing down. Shift to a lower gear when you
go down a steep or long hill.
{CAUTION:
If you do not shift down, your brakes could
get so hot that they would not work well.
You would then have poor braking or even
none going down a hill. You could crash.
Shift down to let your engine assist your
brakes on a steep downhill slope.
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Winter DrivingHere are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies
in your vehicle.
Also seeTires on page 5-55.
Include an ice scraper, a small brush or broom, a supply
of windshield washer uid, a rag, some winter outer
clothing, a small shovel, a ashlight, a red cloth and
reective warning triangles. And, if you will be driving
under severe conditions, include a small bag of sand,
a piece of old carpet or a couple of burlap bags to help
provide traction. Be sure you properly secure these items
in your vehicle.
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Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires
and the road, you can have a very slippery situation.
You will have a lot less traction or “grip” and will need
to be very careful.What is 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 is
about freezing (32°F; 0°C) 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.
If you have traction assist, keep the system on. It will
improve your ability to accelerate when driving on a
slippery road. But you can turn the traction system off if
your vehicle ever gets stuck in sand, mud, ice or snow.
SeeIf You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-44. Even though your vehicle has a traction
system, you will want to slow down and adjust your
driving to the road conditions. SeeTraction Assist
System (TAS) on page 4-9.
If you do not have a traction system, 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.
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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.
If You Are Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you do not want to spin your
wheels too fast. The method known as “rocking” can help
you get out when you are stuck, but you must use
caution.
{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 re or other damage.
When you are stuck, spin the wheels as little
as possible. Do not spin the wheels above
35 mph (55 km/h) as shown on the
speedometer.
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, seeTire Chains on page 5-71.
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The Tire and Loading Information label also tells you
the size and recommended ination pressure for
the original equipment tires on your vehicle. For more
information on tires and ination seeTires on page 5-55
andInation - Tire Pressure on page 5-64.
If your vehicle does not have the Tire and Loading
Information label, the Certication/Tire label shows the
tire size and recommended ination pressures needed to
obtain the Gross Vehicle Weight Rating (GVWR) and the
Gross Axle Weight Rating (GAWR) for the front and rear
axles. See “Certication/Tire Label” later in this section.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined weight of
occupants and cargo should never exceed
XXX pounds” on your vehicle placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and
passengers from XXX kilograms or XXX pounds.4. The resulting gure equals the available amount of
cargo and luggage load capacity. For example,
if the “XXX” amount equals 1400 lbs. and there will
be ve 150 lb. passengers in your vehicle, the
amount of available cargo and luggage load capacity
is 650 lbs. (1400−750 (5 x 150) = 650 lbs.).
5. Determine the combined weight of luggage and
cargo being loaded on the vehicle. That weight
may not safely exceed the available cargo
and luggage load capacity calculated in Step 4.
6. If your vehicle will be towing a trailer, the load from
your trailer will be transferred to your vehicle.
Consult this manual to determine how this reduces
the available cargo and luggage load capacity of
your vehicle.
SeeTowing a Trailer on page 4-55for important
information on towing a trailer, towing safety rules
and trailering tips.
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Loading Your Vehicle
Item Description Total
AVehicle Capacity
Weight for Example 3=1,000 lbs (453 kg)
BSubtract Occupant
Weight 200 lbs
(91 kg)×5=1,000 lbs (453 kg)
CAvailable Cargo
Weight =0 lbs (0 kg)
Refer to your vehicle’s tire and loading information label
for specic information about your vehicle’s capacity
weight and seating positions. The combined weight of the
driver, passengers and cargo should never exceed your
vehicle’s capacity weight.
Certication/Tire Label
The Certication/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 ination 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 Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR). To nd 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. Example 3
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Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
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:
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. See “Hitches” later
in this section.
Don’t tow a trailer at all during the rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 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 can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary,
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
Look in the following chart to nd the maximum trailer
weight for your vehicle.
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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.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You’ll nd these numbers on the
Certication label at the rear edge of the driver’s door or
see Loading Your Vehicle for more information. Then,
be sure you don’t go over the GVW limit for your vehicle,
or the GAWR, including the weight of the trailer tongue.
If you use a weight distributing hitch, make sure you don’t
go over the rear axle limit before you apply the weight
distribution spring bars.
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.
Weight Distributing Hitches and Weight
Carrying Hitches
When using a weight-distributing hitch, the hitch must
be adjusted so the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.
If you use a step-bumper hitch, the bumper could
be damaged in sharp turns. Make sure there is ample
room when turning to avoid contact between the
trailer and the bumper.(A) Body to Ground Distance, (B) Front of Vehicle
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