2006 GMC YUKON Engine

Ease up on your speed as you approach the
top of the hill.
Attach a ag to the vehicle to make you more
visible to approaching traffic on trails or hills.
Sound the horn as you approach the top of the
hill to let opposing traffic know you are there.
Use your headlamps even during the day.
They make you more visible to oncoming traffic.
{CAUTION:
Driving to the top (crest) of a hill at full speed
can cause an accident. There could be a
drop-off, embankment, cliff, or even another
vehicle. You could be seriously injured or
killed. As you near the top of a hill, slow
down and stay alert.
Q:What should I do if my vehicle stalls, or is about
to stall, and I cannot make it up the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here is what youshoulddo:
Push the brake pedal to stop the vehicle and
keep it from rolling backwards. Also, apply the
parking brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If your engine has stopped running, you will need
to restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission
to PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible
in REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you will be able to tell if your wheels are
straight and maneuver as you back down. It is
best that you back down the hill with your wheels
straight rather than in the left or right direction.
Turning the wheel too far to the left or right
will increase the possibility of a rollover.
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Here are some things youmust notdo if you stall,
or are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL (N) to rev-up the engine and regain
forward momentum. This will not work. Your
vehicle will roll backwards very quickly and you
could go out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift
to REVERSE (R), release the parking brake,
and slowly back straight down.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). This is because
the NEUTRAL position on the transfer case
overrides the transmission. You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift
the transmission to PARK (P). But do not shift
the transfer case to NEUTRAL.
Never attempt to turn around if you are about
to stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep enough to
cause you to roll over if you turn around. If you
cannot make it up the hill, you must back straight
down the hill.
Q:Suppose, after stalling, I try to back down
the hill and decide I just cannot do it.
What should I do?
A:Set the parking brake, put your transmission in
PARK (P) and turn off the engine. Leave the
vehicle and go get some help. Exit on the uphill
side and stay clear of the path the vehicle would
take if it rolled downhill. Do not shift the transfer
case to NEUTRAL when you leave the vehicle.
Leave it in some gear.
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Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
How steep is the downhill? Will I be able to
maintain vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a
hidden creek bank or even a river bottom with
large rocks?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help your brakes
and they will not have to do all the work. Descend
slowly, keeping your vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade.
This could cause loss of control and a
serious accident. Apply the brakes lightly
when descending a hill and use a low gear
to keep vehicle speed under control.
Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident.
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work and
could overheat and fade.
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Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill.
But if it happens going downhill, here is what to do.
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) and, while still braking, restart
the engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go
across the incline of a hill. If this happens, you have
to decide whether to try to drive across the incline.
Here are some things to consider:
A hill that can be driven straight up or down
may be too steep to drive across. When you
go straight up or down a hill, the length of the
wheel base — the distance from the front wheels
to the rear wheels — reduces the likelihood
the vehicle will tumble end over end.But when you drive across an incline, the much
more narrow track width — the distance between
the left and right wheels — may not prevent
the vehicle from tilting and rolling over. Also,
driving across an incline puts more weight on the
downhill wheels. This could cause a downhill
slide or a rollover.
Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill. If the vehicle slips sideways,
it can hit something that will trip it — a rock,
a rut, etc. — and roll over.
Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock
with the uphill wheels, or if the downhill wheels
drop into a rut or depression, your vehicle can
tilt even more.
For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because
the trail goes across the incline does not mean you
have to drive it. The last vehicle to try it might
have rolled over.
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Driving in Water
Heavy rain can mean ash ooding, and ood waters
demand extreme caution.
Find out how deep the water is before you drive through
it. If it is deep enough to cover your wheel hubs,
axles or exhaust pipe, do not try it — you probably will
not get through. Also, water that deep can damage
your axle and other vehicle parts.
If the water is not too deep, drive slowly through it. At
faster speeds, water splashes on your ignition system
and your vehicle can stall. Stalling can also occur if you
get your tailpipe under water. And, as long as your
tailpipe is under water, you will never be able to start
your engine. When you go through water, remember that
when your brakes get wet, it may take you longer to stop.
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only shallow
CAUTION: (Continued)
CAUTION: (Continued)
water, it can still wash away the ground
from under your tires, and you could lose
traction and roll the vehicle over. Do not
drive through rushing water.
SeeDriving in Rain and on Wet Roads on page 4-32
for more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on
the underbody, chassis or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
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Hydroplaning
Hydroplaning is dangerous. So much water can build
up under your tires that they can actually ride on
the water. This can happen if the road is wet enough
and you are going fast enough. When your vehicle
is hydroplaning, it has little or no contact with the road.
Hydroplaning does not happen often. But it can if
your tires do not have much tread or if the pressure in
one or more is low. It can happen if a lot of water is
standing on the road. If you can see reections
from trees, telephone poles, or other vehicles, and
raindrops dimple the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds. There
just is not a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine. Never drive through water that is
slightly lower than the underbody of your vehicle.
If you cannot avoid deep puddles or standing water,
drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through owing water, as
you might at a low water crossing, your vehicle
can be carried away. As little as six inches
of owing water can carry away a smaller
vehicle. If this happens, you and other vehicle
occupants could drown. Do not ignore police
warning signs, and otherwise be very cautious
about trying to drive through owing water.
Some Other Rainy Weather Tips
Turn on your low-beam headlamps — not just
your parking lamps — to help make you more
visible to others.
Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
Have good tires with proper tread depth.
SeeTires on page 5-57.
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Once you are moving on the freeway, make certain
you allow a reasonable following distance. Expect
to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit,
do not, under any circumstances, stop and back up.
Drive on to the next exit.
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 are ready. Try to be well rested. If you
must start when you are not fresh — such as after
a day’s work — do not plan to make too many miles
that rst 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 is ready to go. If it needs
service, have it done before starting out. Of course,
you will nd experienced and able service experts in
GM dealerships all across North America. They will 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 inated to
the recommended pressure?
Weather Forecasts:What is 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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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.
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