Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not 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 overdriving
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, the wheels are
not 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.A cornering skid is best handled by easing your foot off
the accelerator pedal.
If you have the Traction Control System (TCS),
remember: It helps avoid only the acceleration skid. See
Traction Control System (TCS) on page 4-8. 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.
Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety, you
will 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 reducing vehicle speed 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 mirrored surface — and slow
down when you have any doubt.
4-12
If you have the Antilock Brake System (ABS),
remember: It helps avoid only the braking skid. If you do
not have ABS, then in a braking skid, where the
wheels are no longer rolling, release enough pressure
on the brakes to get the wheels rolling again. This
restores steering control. Push the brake pedal down
steadily when you have to stop suddenly. As long as the
wheels are rolling, you will have steering control.
Driving at Night
Night driving is more dangerous than day driving
because some drivers are likely to be impaired — by
alcohol or drugs, with night vision problems, or by
fatigue.
Night driving tips include:
•Drive defensively.
•Do not drink and drive.
•Reduce headlamp glare by adjusting the inside
rearview mirror.
•Slow down and keep more space between you and
other vehicles because your headlamps can only
light up so much road ahead.
•Watch for animals.
•When tired, pull off the road.
•Do not wear sunglasses.
•Avoid staring directly into approaching headlamps.
•Keep the windshield and all glass on your vehicle
clean — inside and out.
•Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
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If your vehicle has the Traction Control System (TCS), it
improves your ability to accelerate when driving on a
slippery road. But you can turn the TCS off if you ever
need to. You should turn the system off if your
vehicle ever gets stuck in sand, mud, ice, or snow. See
If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 4-19. Even though your vehicle has TCS, slow
down and adjust your driving to the road conditions.
Under certain conditions, you might want to turn the TCS
off, such as when driving through deep snow and
loose gravel, to help maintain vehicle motion at lower
speeds. SeeTraction Control System (TCS) on
page 4-8.
If your vehicle does not have TCS, 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.
Unless your vehicle has the Antilock Brake System
(ABS), you will want to brake very gently, too. If you do
have ABS, seeAntilock Brake System (ABS) on
page 4-5. ABS improves your vehicle’s stability when
you make a hard stop on a slippery road. Whether your
vehicle has ABS or not, begin stopping sooner than
you would on dry pavement. Without ABS, if you
feel your vehicle begin to slide, let up on the brakes a
little. Push the brake pedal down steadily to get the most
traction you can.Remember, unless your vehicle has ABS, if you brake
so hard that the wheels stop rolling, you will just
slide. Brake so the wheels always keep rolling and you
can still steer.
•Whatever your vehicle’s braking system, allow
greater following distance on any slippery road.
•Watch for slippery spots. The road might be fine
until you hit a spot that is covered with ice. On
an otherwise clear road, ice patches can 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 can 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.
4-17
Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right to clear
the area around the front wheels. For four-wheel-drive
vehicles, shift into 4HI. SeeFour-Wheel Drive on
page 2-32. Turn off any traction system. SeeTraction
Control System (TCS) on page 4-8. Then shift back and
forth between REVERSE (R) and a forward gear, or
with a manual transmission, between FIRST (1)
or SECOND (2) and REVERSE (R), spinning the wheels
as little as possible. To prevent transmission wear,
wait until the wheels stop spinning before shifting gears.
Release the accelerator pedal while you shift, and
press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning the wheels in
the forward and reverse directions, you will cause a
rocking motion that could free your vehicle. If that does
not get your vehicle out after a few tries, it might
need to be towed out. If your vehicle does need to be
towed out, seeTowing Your Vehicle on page 4-24.
Tow 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 tow hooks to tow the vehicle.
Your vehicle could be damaged and it would not be
covered by warranty.
4-20
Item Number Item Remarks
1 Brake Camshaft** One fitting each (apply sparingly).
2 Steering Column Slip Joint* One fitting.
3 Steering Drag Link Ends One fitting each end.
4 Pivot Points and Hinges Apply chassis lubricant.
5 Pivot Points and Hinges Apply chassis lubricant.
6 Slack Adjuster** One fitting.
7Brake Cam Roller Pins at interface of pin
and shoe**Apply engine oil.
8 Front Steering KnucklesOne fitting each side, lower bushing.
(Hand-operated grease gun only) Hand-pack upper
bearing.
9 Front Wheel Bearings Hand-pack or lubricate.
10 Steering Tie Rod Ends One fitting each end.
11 Spring Slip Pads* (Multi-Leaf Only) Apply chassis lubricant.
12 Clutch Release Bearing* Cup or fitting.
13 Battery Terminal (except “ST” type) Keep coated with petroleum jelly.
14 Transmission Fill to level of filler plug.
5-63
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned at the
factory to give you the longest tire life and best overall
performance.
Proper front wheel alignment must be maintained in
order to ensure efficient steering, good directional
stability, and prevent abnormal tire wear. If you notice
unusual tire wear or your vehicle is pulling one way
or the other, the alignment may need to be reset. If you
notice your vehicle vibrating when driving on a smooth
road, your wheels may need to be balanced.
Tightening the Wheel Nuts
{CAUTION:
Wheel nuts that are not tight can work loose. If
all the nuts on a wheel come off, the wheel can
come off the vehicle, causing a crash. All
wheel nuts must be properly tightened. Follow
the rules in this section to be sure they are.
This section lets you know how often to check the
tightness of the wheel nuts on your vehicle and how tight
they must be.First, use these pictures to decide what kind of wheels
you have.
Then, refer to the following steps for the wheels
you have.Hub-Piloted Type,
8-Hole
Hub-Piloted Type,
10-Hole
5-86
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your tires properly. If air goes
out of a tire, it is much more likely to leak out slowly. But if
you should ever have a blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly. Steer
to maintain lane position, and then gently brake to a stop
well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop –– well off the road if possible.
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place and turn on your
hazard warning flashers. SeeHazard Warning Flashers
on page 3-6.
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❑Clean air brake application valve (or every 3 months,
or every 300 hours, whichever occurs first). Lubricate
linkage.
❑Air brake chamber service (or every 2 months,
whichever occurs first).(34)
15,000 Miles (24 000 km)
❑Gasoline Engine Only: Check engine oil life system.
If engine oil and filter are changed, reset system.
See “Engine Oil (Gasoline Engine)” in the
Index.(2) (8)
❑DURAMAX
®/Isuzu Diesel Without Engine Oil Life
System Only: Change engine oil and filter (or every
12 months, or every 750 hours of engine operation,
whichever occurs first).(2) (39)
❑DURAMAX
®/Isuzu Diesel With Engine Oil Life System
Only: Check oil life system. If engine oil and filter are
changed, reset system. See “Engine Oil
(DURAMAX
®/Isuzu Diesel)” in the Index.(2) (9)
❑Chassis lubrication service (or every 6 months,
whichever occurs first).(11)
❑Check fluid levels (or every 3 months, whichever
occurs first).(1) (5)
❑Gasoline Engine: Inspect engine air cleaner filter.
If necessary, replace the filter. If vehicle is driven in
dusty/dirty conditions, inspect filter at every engine oil
change. SeeEngine Air Cleaner/Filter on page 5-39
for more information.❑Diesel Engine: Inspect engine air cleaner filter change
indicator. If necessary, replace the filter. If vehicle is
driven in dusty/dirty conditions, inspect filter change
indicator at every engine oil change. SeeEngine Air
Cleaner/Filter on page 5-39for more information.
❑DURAMAX
®/Isuzu Diesel Only: Replace fuel filter (or
every 750 hours of engine operation, whichever
occurs first).
❑Steering system service.(12)
❑Front and rear suspension service.(13)
❑Spring-to-axle U-bolts and shackle bolts service.(15)
❑Exhaust system service (or every 6 months, whichever
occurs first).(2) (3) (16)
❑Wheels and tires service.(14)
❑Hydraulic brake service (or every 6 months, whichever
occurs first).(6) (36)
❑Parking brake service (or every 6 months, whichever
occurs first).(21)
❑Air brake service (or every 6 months, whichever
occurs first).(32)
❑Air brake automatic slack adjuster service (or every
500 hours, whichever occurs first).(33)
❑Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours, whichever
occurs first).
6-6