2009 GMC SAVANA engine

Braking
SeeBrake System Warning Light on page 3-33.
Braking action involves perception time and reaction
time. First, you have to decide to push on the brake
pedal. That is perception time. Then you have to bring
up your foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination, and eyesight all play a part. So do alcohol,
drugs, and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
your vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road, whether it is pavement or
gravel; the condition of the road, whether it is wet, dry, or
icy; tire tread; the condition of the brakes; the weight of
the vehicle; and the amount of brake force applied.Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. The brakes might not have time to cool
between hard stops. The brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your vehicle’s engine ever stops while you are driving,
brake normally but do not pump the brakes. If you do,
the pedal could get harder to push down. If the
engine stops, you will still have some power brake
assist. But you will use it when you brake. Once the
power assist is used up, it can take longer to stop and
the brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-3.
4-4

Antilock Brake System (ABS)
Your vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help prevent
a braking skid.
When you start the engine and begin to drive away,
ABS will check itself. You might hear a momentary
motor or clicking noise while this test is going on. This
is normal.
If there is a problem with
the ABS, this warning light
will stay on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-34.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
you steer around the obstacle while braking hard.
As you brake, the computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.
Remember: ABS does not change the time you need to
get your foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, you will not have time to apply the brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you
have ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal down
firmly and let antilock work for you. You might feel the
brakes vibrate or notice some noise, but this is normal.
Braking in Emergencies
With ABS, you can steer and brake at the same time.
In many emergencies, steering can help you more than
even the very best braking.
4-5

For your safety, the system can only be disabled when
the vehicle speed is less than 20 mph (32 km/h).
Three chimes will be heard and the StabiliTrak light
comes on.
To turn on the StabiliTrak system, press the StabiliTrak
button again. StabiliTrak will automatically turn back on
when the vehicle speed exceeds 20 mph (32 km/h).
One chime is heard and the StabiliTrak light will turn off.
When the StabiliTrak system has been turned off,
system noises may still be heard as a result of the
brake-traction control coming on.
It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn the
system off if the vehicle is stuck in sand, mud, ice or
snow, and you want to “rock” the vehicle to attempt to
free it. SeeIf Your Vehicle is Stuck in Sand, Mud, Ice, or
Snow on page 4-17.
StabiliTrak System Operation
The StabiliTrak system is normally on, except when
the system is initializing or has been disabled with
the StabiliTrak button. The StabiliTrak system will
automatically activate to assist the driver in maintaining
vehicle directional control in most driving conditions.When activated, the StabiliTrak system may reduce
engine power to the wheels and apply braking to
individual wheels as necessary to assist the driver
with vehicle directional control. If cruise control is being
used when StabiliTrak activates, the cruise control
automatically disengages. The cruise control can be
re-engaged when road conditions allow. SeeCruise
Control on page 3-10.
The StabiliTrak system may also turn off automatically
if it determines that a problem exists with the system.
If the problem does not clear itself after restarting
the vehicle, see your dealer/retailer for service.
Traction Control Operation
The traction control system is part of the StabiliTrak
system. Traction control limits wheel spin by reducing
engine power to the wheels and by applying brakes
to each individual wheel as necessary.
If the brake-traction control system activates constantly
or if the brakes have heated up due to high speed
braking, the brake-traction control will be automatically
disabled. The system will come back on after the
brakes have cooled. This can take up to two minutes
or longer depending on brake usage.
4-7

The traction control system may activate on dry or rough
roads or under conditions such as heavy acceleration
while turning or abrupt upshifts/downshifts of the
transmission. When this a reduction in acceleration
may be noticed, or a noise or vibration may be heard.
This is normal.
Adding non-dealer/non-retailer accessories can affect
the vehicle’s performance. SeeAccessories and
Modifications on page 5-3for more information.
Locking Rear Axle
Vehicles with a locking rear axle can give more traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when traction is low,
this feature will allow the rear wheel with the most
traction to move the vehicle.
All-Wheel Drive (AWD) System
If the vehicle has this feature, engine power is sent to
all four wheels when extra traction is needed. This is
like four-wheel drive, but there is no separate lever
or switch to engage or disengage the front axle.
It is fully automatic, and adjusts itself as needed for
road conditions.
Steering
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and your speed. While in a curve, speed is the
one factor you can control.
If you need to reduce speed, do it before you enter the
curve, while the front wheels are straight ahead.
Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait
to accelerate until you are out of the curve, and then
accelerate gently into the straightaway.
4-8

Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they 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.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
•Allow extra following distance.
•Pass with caution.
•Keep windshield wiping equipment in good shape.
•Keep the windshield washer fluid reservoir filled.
•Have good tires with proper tread depth. SeeTires
on page 5-54.
•Turn off cruise control.
Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
•Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
•Wiper Blades:In good shape?
•Fuel, Engine Oil, Other Fluids:All levels checked?
•Lamps:Do they all work and are lenses clean?
•Tires:Are treads good? Are tires inflated to
recommended pressure?
•Weather and Maps:Safe to travel? Have
up-to-date maps?
4-13

Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, find a safe
place to park your vehicle and rest.
Other driving tips include:
•Keep the vehicle well ventilated.
•Keep interior temperature cool.
•Keep your eyes moving — scan the road ahead
and to the sides.
•Check the rearview mirror and vehicle instruments
often.
Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on flat or rolling terrain. Tips for driving
in these conditions include:
•Keep the vehicle serviced and in good shape.
•Check all fluid levels and brakes, tires, cooling
system, and transmission.
•Going down steep or long hills, shift to a
lower gear.
{CAUTION:
If you do not shift down, the 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 the engine
assist the brakes on a steep downhill slope.
4-14

{CAUTION:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and 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 the engine running
and the vehicle in gear when going downhill.
•Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
•Top of hills: Be alert — something could be in your
lane (stalled car, accident).
•Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow or ice between the
tires and the road, creating less traction or grip. Wet ice
can occur at about 32°F (0°C) when freezing rain begins
to fall, resulting in even less traction. Avoid driving on wet
ice or in freezing rain until roads can be treated with salt
or sand.
Drive with caution, whatever the condition. Accelerate
gently so traction is not lost. Accelerating too quickly
causes the wheels to spin and makes the surface under
the tires slick, so there is even less traction.
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.
TheAntilock Brake System (ABS) on page 4-5improves
vehicle stability during hard stops on a slippery roads, but
apply the brakes sooner than when on dry pavement.
Allow greater following distance on any slippery road
and watch for slippery spots. Icy patches can occur on
otherwise clear roads in shaded areas. The surface of
a curve or an overpass can remain icy when the
surrounding roads are clear. Avoid sudden steering
maneuvers and braking while on ice.
Turn off cruise control, if equipped, on slippery surfaces.
4-15

Blizzard Conditions
Being stuck in snow can be in a serious situation. Stay
with the vehicle unless there is help nearby. If possible,
use theRoadside Assistance Program on page 7-7.
To get help and keep everyone in the vehicle safe:
•Turn on theHazard Warning Flashers on page 3-6.
•Tie a red cloth to an outside mirror.
{CAUTION:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside. Engine
exhaust contains carbon monoxide (CO) which
cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
•Clear away snow from around the base of your
vehicle, especially any that is blocking the
exhaust pipe and/or the fuel operated heater
exhaust system, if equipped. If the vehicle has
a diesel engine and a fuel operated heater, see
“Fuel Operated Heater (FOH)” in the diesel
engine supplement.
CAUTION: (Continued)
CAUTION: (Continued)
•
Check again from time to time to be sure
snow does not collect there.
•Open a window about two inches on the side
of the vehicle that is away from the wind to
bring in fresh air.
•Fully open the air outlets on or under the
instrument panel.
•Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting.
See Climate Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-30.
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 the exhaust.
Run the engine for short periods only as needed to
keep warm, but be careful.
4-16