GMC YUKON XL 2007 Owners Manual

Highway Hypnosis
Is there actually such a condition as highway
hypnosis? Or is it just plain falling asleep at the
wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road
with the same scenery, along with the hum of
the tires on the road, the drone of the engine, and
the rush of the wind against the vehicle that
can make you sleepy. Do not let it happen to you!
If it does, your vehicle can leave the road in
less than a second, and you could crash and be
injured.What can you do about highway hypnosis? First,
be aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with
a comfortably cool interior.
Keep your eyes moving. Scan the road ahead
and to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get
some exercise, or both. For safety, treat
drowsiness on the highway as an emergency.
381

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 on page 356for 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.
{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.
382

{CAUTION:
Coasting downhill in NEUTRAL (N) or with
the ignition off is dangerous. Your brakes
will have to do all the work of slowing
down. They 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. Always have your
engine running and your vehicle in gear
when you go downhill.
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.
Know how to go uphill. You may want to shift
down to a lower gear. The lower gears help
cool your engine and transmission, and you can
climb the hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at
speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled
car or an accident.
You may see highway signs on mountains that
warn of special problems. Examples are long
grades, passing or no-passing zones, a falling
rocks area, or winding roads. Be alert to these
and take appropriate action.
383

Winter Driving
Here 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 482.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 a couple of 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.
Driving on Snow or Ice
Most of the time, those places where the tires
meet the road probably have good traction.
However, if there is snow or ice between the 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.
384

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.
StabiliTrak
®will improve your ability to accelerate
when driving on a slippery road. But you can
turn StabiliTrak
®off if you ever need to. See
StabiliTrak®System on page 348andIf Your
Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 388. Even with StabiliTrak
®, you will want to
slow down and adjust your driving to the road
conditions. Under certain conditions, you may want
to turn StabiliTrak
®off, such as when driving
through deep snow and loose gravel, to help
maintain vehicle motion at lower speeds.
Your Anti-Lock Brake System (ABS) improves
your vehicle’s stability when you make a hard stop
on a slippery road. Even though you have ABS,
you will want to begin stopping sooner than
you would on dry pavement. SeeAnti-Lock Brake
System (ABS) on page 345.
385

Allow greater following distance on any
slippery road.
Watch for slippery spots. The road might be
ne until you hit a spot that is covered with ice.
On an otherwise clear road, ice patches may
appear in shaded areas where the sun cannot
reach, such as 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 are
actually on the ice, and avoid sudden steering
maneuvers.
If You Are Caught in a Blizzard
If you are stopped by heavy snow, you could be in
a serious situation. You should probably stay
with your vehicle unless you know for sure that you
are near help and you can hike through the
snow. Here are some things to do to summon
help and keep yourself and your passengers safe:
Turn on your hazard ashers.
Tie a red cloth to your vehicle to alert police
that you have been stopped by the snow.
Put on extra clothing or wrap a blanket around
you. If you do not have blankets or extra
clothing, make body insulators from
newspapers, burlap bags, rags, oor
mats — anything you can wrap around yourself
or tuck under your clothing to keep warm.
You can run the engine to keep warm, but be
careful.
386

{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 cannot 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
does not collect there.
Open a window just a little on the side of
the vehicle that is 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.
387

If Your Vehicle is 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 more information about using tire chains on
your vehicle, seeTire Chains on page 506.
Rocking Your Vehicle to Get It Out
First, turn your steering wheel left and right. That
will clear the area around your front wheels. If you
have a four-wheel-drive vehicle, shift into
Four-Wheel High or Four-Wheel Low. Turn the
StabiliTrak
®System off. SeeStabiliTrak®System
on page 348. Then shift back and forth between
REVERSE (R) and a forward gear, spinning the
wheels as little as possible. Release the accelerator
pedal while you shift, and press lightly on the
accelerator pedal when the transmission is in gear.
By slowly spinning your wheels in the forward and
reverse directions, you will cause a rocking motion
that may free your vehicle. If that does not get you
out after a few tries, you may need to be towed out.
Or, you can use your recovery hooks if your vehicle
has them. If you do need to be towed out, see
Towing Your Vehicle on page 400.
388

Recovery Hooks
{CAUTION:
These hooks, when used, are under a lot
of force. Always pull the vehicle straight
out. Never pull on the hooks at a
sideways angle. The hooks could break
off and you or others could be injured
from the chain or cable snapping back.
Notice:Never use recovery hooks to tow the
vehicle. Your vehicle could be damaged
and it would not be covered by warranty.
Your vehicle may have recovery hooks at the front
of the vehicle. You may need to use them if you
are stuck off-road and need to be pulled to
some place where you can continue driving.
389

Loading Your Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the
vehicle capacity weight and includes the weight of
all occupants, cargo, and all nonfactory-installed
options. Two labels on your vehicle show how
much weight it was designed to carry, the Tire and
Loading Information label and the Certication/Tire
label.
{CAUTION:
Do not load your vehicle any heavier than
the Gross Vehicle Weight Rating (GVWR),
or either the maximum front or rear Gross
Axle Weight Rating (GAWR). If you do,
parts on your vehicle can break, and it
can change the way your vehicle handles.
These could cause you to lose control
and crash. Also, overloading can shorten
the life of your vehicle.
Tire and Loading Information Label
A vehicle specic Tire and Loading Information
label is attached to the center pillar (B-pillar). With
the driver’s door open, you will nd the label
attached below the door lock post (striker). The tire
and loading information label shows the number of
occupant seating positions (A), and the maximum
vehicle capacity weight (B) in kilograms and
pounds.
Label Example
390