1999 GMC SUBURBAN Owner's Manual

4-14
Passing
The driver of a vehicle about to pass another on a
two
-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead, then goes
back into the right lane again. A simple maneuver?
Not necessarily! Passing another vehicle on a two
-lane
highway is a potentially dangerous move, since the
passing vehicle occupies the same lane as oncoming
traffic for several seconds. A miscalculation, an error in
judgment, or a brief surrender to frustration or anger can
suddenly put the passing driver face to face with the
worst of all traffic accidents
-- the head-on collision.
So here are some tips for passing:

ªDrive ahead.º Look down the road, to the sides and
to crossroads for situations that might affect your
passing patterns. If you have any doubt whatsoever
about making a successful pass, wait for a better time.

Watch for traffic signs, pavement markings and lines.
If you can see a sign up ahead that might indicate a
turn or an intersection, delay your pass. A broken
center line usually indicates it's all right to pass
(providing the road ahead is clear). Never cross a solid
line on your side of the lane or a double solid line,
even if the road seems empty of approaching traffic.
Do not get too close to the vehicle you want to pass
while you're awaiting an opportunity. For one thing,
following too closely reduces your area of vision,
especially if you're following a larger vehicle.
Also, you won't have adequate space if the vehicle
ahead suddenly slows or stops. Keep back a
reasonable distance.

When it looks like a chance to pass is coming up,
start to accelerate but stay in the right lane and
don't get too close. Time your move so you will be
increasing speed as the time comes to move into the
other lane. If the way is clear to pass, you will have a
ªrunning startº that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your pass,
you need only slow down and drop back again and
wait for another opportunity.

If other cars are lined up to pass a slow vehicle, wait
your turn. But take care that someone isn't trying to
pass you as you pull out to pass the slow vehicle.
Remember to glance over your shoulder and check
the blind spot.

4-15

Check your mirrors, glance over your shoulder and
start your left lane change signal before moving out
of the right lane to pass. When you are far enough
ahead of the passed vehicle to see its front in your
inside mirror, activate your right lane change signal
and move back into the right lane. (Remember that
if your right outside mirror is convex, the vehicle
you just passed may seem to be farther away from
you than it really is.)

Try not to pass more than one vehicle at a time
on two
-lane roads. Reconsider before passing the
next vehicle.

Don't overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not flashing,
it may be slowing down or starting to turn.

If you're being passed, make it easy for the
following driver to get ahead of you. Perhaps
you can ease a little to the right.
Loss of Control
Let's review what driving experts say about what happens
when the three control systems (brakes, steering and
acceleration) don't have enough friction where the tires
meet the road to do what the driver has asked.
In any emergency, don't give up. Keep trying to
steer and constantly seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking
reasonable care suited to existing conditions, and by
not ªoverdrivingº those conditions. But skids are
always possible.
The three types of skids correspond to your vehicle's
three control systems. In the braking skid, your wheels
aren't rolling. In the steering or cornering skid, too
much speed or steering in a curve causes tires to slip
and lose cornering force. And in the acceleration skid,
too much throttle causes the driving wheels to spin.

4-16
A cornering skid is best handled by easing your foot off
the accelerator pedal. If you have the ªTraction Assist
System,º remember: It helps avoid only the acceleration
skid. If you do not have this system, or if the system is
off, then an acceleration skid is also best handled by
easing your foot off the accelerator pedal.
If your vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want the
vehicle to go. If you start steering quickly enough, your
vehicle may straighten out. Always be ready for a
second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you'll
want to slow down and adjust your driving to these
conditions. It is important to slow down on slippery
surfaces because stopping distance will be longer and
vehicle control more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration or
braking (including engine braking by shifting to a lower
gear). Any sudden changes could cause the tires to
slide. You may not realize the surface is slippery until
your vehicle is skidding. Learn to recognize warning clues -- such as enough
water, ice or packed snow on the road to make a
ªmirrored surfaceº
-- and slow down when you
have any doubt.
Remember: Any anti
-lock brake system (ABS) helps
avoid only the braking skid.
Off-Road Driving with Your
Four
-Wheel-Drive Vehicle
This off-road guide is for vehicles that have
four
-wheel drive.
Also, see ªAnti
-Lock Brakesº in the Index.
If your vehicle doesn't have four
-wheel drive, you
shouldn't drive off
-road unless you're on a level,
solid surface.
Off
-road driving can be great fun. But it does have
some definite hazards. The greatest of these is the
terrain itself.
ªOff
-roadingº means you've left the great North
American road system behind. Traffic lanes aren't
marked. Curves aren't banked. There are no road signs.
Surfaces can be slippery, rough, uphill or downhill.
In short, you've gone right back to nature.

4-17
Off-road driving involves some new skills. And that's
why it's very important that you read this guide. You'll
find many driving tips and suggestions. These will help
make your off
-road driving safer and more enjoyable.
If you think you will need some more ground clearance
at the front of your vehicle, you can easily remove the
front bumper lower air dam.
The front bumper lower air dam is held in place by a
series of push pins located around the lower edge of the
front bumper. The push
-pins are accessible from
underneath the front bumper.The following steps must be performed on each of the
push
-pins to remove the air dam:
1. Insert the blade portion
of a flat
-blade
screwdriver into the
push
-pin slot and pull
downward until the
push
-pin snaps loose.
2. While continuing to
pull downward on the
push
-pin, squeeze and
rotate the expandable
end of the push
-pin
with a pair of pliers
until it releases from
the retainer.

4-18
3. Pull the push-pins and
lower air dam assembly
away from the retainers
until the lower air dam
is free.
When you're back on roads, though, be sure to replace
the air dam.
NOTICE:
Operating your vehicle for extended periods
without the front bumper lower air dam installed
can cause improper air flow to the engine and
may allow things like fog lamps or tow hooks
on the front of your vehicle to be damaged.
Always be sure to replace the front bumper
air dam when you're finished off
-road driving.
To replace the lower air dam:
1. Line up each push-pin
with its intended retainer
and push the washer
portion of the push
-pin
towards the retainer until
it locks into place
2. Push the flat end of the
push
-pin towards the
retainer until it locks
into place, making sure
each is secure.

4-19 Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance and
service work done. Check to make sure all underbody
shields (if so equipped) are properly attached. Be sure
you read all the information about your four
-wheel-drive
vehicle in this manual. Is there enough fuel? Is the spare
tire fully inflated? Are the fluid levels up where they
should be? What are the local laws that apply to
off
-roading where you'll be driving? If you don't know,
you should check with law enforcement people in the
area. Will you be on someone's private land? If so,
be sure to get the necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about
how to load your vehicle.

The heaviest things should be on the load floor and
forward of your rear axle. Put heavier items as far
forward as you can.

Be sure the load is secured properly, so driving on
the off
-road terrain doesn't toss things around.
CAUTION:

Cargo on the load floor piled higher than the
seatbacks can be thrown forward during a
sudden stop. You or your passengers could
be injured. Keep cargo below the top of
the seatbacks.

Unsecured cargo on the load floor can be
tossed about when driving over rough terrain.
You or your passengers can be struck by flying
objects. Secure the cargo properly.

Heavy loads on the roof raise the vehicle's
center of gravity, making it more likely to
roll over. You can be seriously or fatally
injured if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the roof.
Keep cargo in the cargo area as far forward
and low as possible.
You'll find other important information in this manual.
See ªVehicle Loading,º ªLuggage Carrierº and ªTiresº
in the Index.

4-20 Environmental Concerns
Off-road driving can provide wholesome and satisfying
recreation. However, it also raises environmental
concerns. GM recognizes these concerns and urges
every off
-roader to follow these basic rules for
protecting the environment:

Always use established trails, roads and areas that
have been specially set aside for public off
-road
recreational driving; obey all posted regulations.

Avoid any driving practice that could damage
the environment
-- shrubs, flowers, trees,
grasses
-- or disturb wildlife (this includes
wheel
-spinning, breaking down trees or
unnecessary driving through streams or over
soft ground).

Always carry a litter bag . . . make sure all refuse
is removed from any campsite before leaving.

Take extreme care with open fires (where permitted),
camp stoves and lanterns.

Never park your vehicle over dry grass or other
combustible materials that could catch fire from the
heat of the vehicle's exhaust system.
Traveling to Remote Areas
It makes sense to plan your trip, especially when going
to a remote area. Know the terrain and plan your route.
You are much less likely to get bad surprises. Get
accurate maps of trails and terrain. Try to learn of any
blocked or closed roads.
It's also a good idea to travel with at least one other
vehicle. If something happens to one of them, the other
can help quickly.
Does your vehicle have a winch? If so, be sure to read
the winch instructions. In a remote area, a winch can be
handy if you get stuck. But you'll want to know how to
use it properly.
Getting Familiar with Off-Road Driving
It's a good idea to practice in an area that's safe and
close to home before you go into the wilderness.
Off
-road driving does require some new and different
driving skills. Here's what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen for
unusual tire or engine sounds. With your arms, hands,
feet and body, you'll need to respond to vibrations and
vehicle bounce.

4-21
Controlling your vehicle is the key to successful
off
-road driving. One of the best ways to control your
vehicle is to control your speed. Here are some things to
keep in mind. At higher speeds:

you approach things faster and you have less time
to scan the terrain for obstacles.

you have less time to react.

you have more vehicle bounce when you drive
over obstacles.

you'll need more distance for braking, especially
since you're on an unpaved surface.
CAUTION:
When you're driving off-road, bouncing and
quick changes in direction can easily throw you
out of position. This could cause you to lose
control and crash. So, whether you're driving on
or off the road, you and your passengers should
wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain and its
many different features. Here are some things to consider.
Surface Conditions. Off
-roading can take you over
hard
-packed dirt, gravel, rocks, grass, sand, mud,
snow or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle in different
ways. Depending upon the kind of surface you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction and longer
braking distances.
Surface Obstacles. Unseen or hidden obstacles can be
hazardous. A rock, log, hole, rut or bump can startle you
if you're not prepared for them. Often these obstacles are
hidden by grass, bushes, snow or even the rise and fall of
the terrain itself. Here are some things to consider:

Is the path ahead clear?

Will the surface texture change abruptly up ahead?

Does the travel take you uphill or downhill?
(There's more discussion of these subjects later.)

Will you have to stop suddenly or change
direction quickly?