GMC T-Series 1999 User manual

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The 1999 GMC T-Series Owner’s Manual
1-1 Seats and Restraint Systems
This section tells you how to use your seats and safety belts properly.
2-1 Features and Controls
This section explains how to start and operate your vehicle.
3-1 Comfort Controls and Audio Systems
This section tells you how to adjust the ventilation and comfort controls and how to operate your audio system.
4-1 Your Driving and the Road
Here you’ll find helpful information and tips about the road and how to drive under different conditions.
5-1 Problems on the Road
This section tells you what to do if you have a problem while driving, such as a flat tire or overheated engine, etc.
6-1 Service and Appearance Care
Here the manual tells you how to keep your vehicle running properly and looking good.
7-1 Maintenance Schedule
This section tells you when to perform vehicle maintenance and what fluids and lubricants to use.
8-1 Customer Assistance Information
This section tells you how to contact GMC for assistance and how to get service and owner publications.
It also gives you information on “Reporting Safety Defects” on page 8-6.
9-1 Index
Here’s an alphabetical listing of almost every subject in this manual. You can use it to quickly find
something you want to read.

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GENERAL MOTORS, GM, the GM Emblem, GMC
and the GMC Emblem are registered trademarks of
General Motors Corporation.
This manual includes the latest information at the time
it was printed. We reserve the right to make changes
in the product after that time without further notice.
For vehicles first sold in Canada, substitute the name
“General Motors of Canada Limited” for GM Medium
Duty Truck Division whenever it appears in this manual.
Please keep this manual in your vehicle, so it will be
there if you ever need it when you’re on the road. If you
sell the vehicle, please leave this manual in it so the new
owner can use it.
We support voluntary
technician certification.
For Canadian Owners Who Prefer a
French Language Manual:
Aux propriétaires canadiens: Vous pouvez vous
procurer un exemplaire de ce guide en français chez
votre concessionaire ou au:
DGN Marketing Services Ltd.
1577 Meyerside Dr.
Mississauga, Ontario L5T 1B9
Litho in U.S.A.
E
Copyright General Motors Corporation 1998
X9903 A First Edition All Rights Reserved

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How to Use this Manual
Many people read their owner’s manual from beginning
to end when they first receive their new vehicle. If
you do this, it will help you learn about the features
and controls for your vehicle. In this manual, you’ll
find that pictures and words work together to explain
things quickly.
Index
A good place to look for what you need is the Index in
back of the manual. It’s an alphabetical list of what’s in
the manual, and the page number where you’ll find it.
Safety Warnings and Symbols
You will find a number of safety cautions in this book.
We use a box and the word CAUTION to tell you
about things that could hurt you if you were to ignore
the warning.
CAUTION:
These mean there is something that could hurt
you or other people.
In the caution area, we tell you what the hazard is. Then
we tell you what to do to help avoid or reduce the hazard.
Please read these cautions. If you don’t, you or others
could be hurt.
You will also find a circle
with a slash through it in
this book. This safety
symbol means “Don’t,”
“Don’t do this” or “Don’t
let this happen.”

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Vehicle Damage Warnings
Also, in this book you will find these notices:
NOTICE:
These mean there is something that could
damage your vehicle.
In the notice area, we tell you about something that can
damage your vehicle. Many times, this damage would
not be covered by your warranty, and it could be costly.
But the notice will tell you what to do to help avoid
the damage.
When you read other manuals, you might see
CAUTION and NOTICE warnings in different colors or
in different words.
You’ll also see warning labels on your vehicle. They use
the same words, CAUTION or NOTICE.

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For example,
these symbols
are used on an
original battery:
CAUTION
POSSIBLE
INJURY
PROTECT
EYES BY
SHIELDING
CAUSTIC
BATTERY
ACID COULD
CAUSE
BURNS
AVOID
SPARKS OR
FLAMES
SPARK OR
FLAME
COULD
EXPLODE
BATTERY
These symbols
are important
for you and
your passengers
whenever your
vehicle is
driven:
DOOR LOCK
UNLOCK
FASTEN
SEAT
BELTS
POWER
WINDOW
AIR BAG
These symbols
have to do with
your lamps:
MASTER
LIGHTING
SWITCH
TURN
SIGNALS
PARKING
LAMPS
HAZARD
WARNING
FLASHER
DAYTIME
RUNNING
LAMPS
FOG LAMPS
These symbols
are on some of
your controls:
WINDSHIELD
WIPER
WINDSHIELD
WASHER
WINDSHIELD
DEFROSTER
REAR
WINDOW
DEFOGGER
VENTILATING
FAN
These symbols
are used on
warning and
indicator lights:
ENGINE
COOLANT
TEMP
BATTERY
CHARGING
SYSTEM
BRAKE
COOLANT
ENGINE OIL
PRESSURE
ANTI-LOCK
BRAKES
Here are some
other symbols
you may see:
FUSE
LIGHTER
HORN
SPEAKER
FUEL
Vehicle Symbols
These are some of the symbols you may find on your vehicle.

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Model Reference
This manual contains information which covers tilt
cab models as shown. Most models are unfinished
from the factory.
Since T-Series models delivered from the factory are
finished in a variety of ways by a number of companies,
you’ll probably find other manuals in your finished
vehicle. These manuals are put there by the companies
that have added components or equipment to the
T-Series model. Read all these materials -- as well as
this manual -- carefully, to get all of the information on
your vehicle.

1-
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1-1
Section 1 Seats and Restraint Systems
Here you’ll find information about the seats in your vehicle and how to use your safety belts properly. You can also
learn about some things you should not do with safety belts.
1-2 Seats and Seat Controls
1-4 Safety Belts: They’re for Everyone
1-8 Here are Questions Many People Ask About
Safety Belts -- and the Answers
1-9 How to Wear Safety Belts Properly
1-9 Driver Position
1-15 Safety Belt Use During Pregnancy
1-16 Right Passenger Position
1-16 Center Passenger Position (If Equipped)
1-17 Children
1-20 Child Restraints
1-27 Larger Children
1-30 Safety Belt Extender
1-30 Checking Your Restraint System
1-30 Replacing Restraint System Parts After
a Crash

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1-2
Seats and Seat Controls
This section tells you about the seats in your vehicle and
how to adjust them properly.
Bucket Seats
Your vehicle has bucket
seats. You can adjust
the driver’s seat with
these levers at the front
of the seat.
Slide lever (A) to the left to unlock the seat and slide the
seat to where you want it. Then, release the lever and try
to move the seat with your body, to make sure the seat is
locked into place.
To adjust the lower seat cushion forward or backward,
pull up on lever (B) and slide the cushion to where you
want it. Then release the lever.
To tilt the seatback, turn the
backrest tilt knob. The knob
is located on the lower
cushion, on the outboard
side of the driver’s seat and
the inboard side of the
passenger’s seat.
To get more support in the
lumbar area of your back,
turn the lumbar adjustment
knob. The knob is located
on the upper cushion, on the
inboard side of the driver’s
seat and the outboard side
of the passenger’s seat.

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CAUTION:
You can lose control of the vehicle if you try to
adjust the seat while the vehicle is moving. The
sudden movement could startle and confuse you,
or make you push a pedal when you don’t want
to. Adjust the driver’s seat only when the vehicle
is not moving.
Head Restraints
Some seats have adjustable head restraints. Slide an
adjustable head restraint up or down so that the top of
the restraint is closest to the top of your ears. This
position reduces the chance of a neck injury in a crash.
Center Seat (If Equipped)
Your vehicle may be equipped with a center seat.
To fold the seatback down,
push the lever located on
the right-hand side of the
seat toward the rear of
the vehicle.
Then lower the seatback forward and push down firmly
to lock in position. A storage compartment is located on
the rear of the seatback for use when the seatback is in
the fully lowered position.
Lift the lever on the right-hand side of the seat and pull
on the seatback when you are ready to raise it.

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Safety Belts: They’re for Everyone
This part of the manual tells you how to use safety belts
properly. It also tells you some things you should not do
with safety belts.
CAUTION:
Don’t let anyone ride where he or she can’t wear
a safety belt properly. If you are in a crash and
you’re not wearing a safety belt, your injuries
can be much worse. You can hit things inside the
vehicle or be ejected from it. You can be seriously
injured or killed. In the same crash, you might
not be if you are buckled up. Always fasten your
safety belt, and check that your passengers’ belts
are fastened properly too.
CAUTION:
It is extremely dangerous to ride in a cargo area,
inside or outside of a vehicle. In a collision,
people riding in these areas are more likely to be
seriously injured or killed. Do not allow people to
ride in any area of your vehicle that is not
equipped with seats and safety belts. Be sure
everyone in your vehicle is in a seat and using a
safety belt properly.
Your vehicle has a light
that comes on as a reminder
to buckle up. (See “Safety
Belt Reminder Light” in
the Index.)

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In most states and Canadian provinces, the law says to
wear safety belts. Here’s why: They work.
You never know if you’ll be in a crash. If you do have
a crash, you don’t know if it will be a bad one.
A few crashes are mild, and some crashes can be so
serious that even buckled up a person wouldn’t survive.
But most crashes are in between. In many of them,
people who buckle up can survive and sometimes walk
away. Without belts they could have been badly hurt
or killed.
After more than 30 years of safety belts in vehicles,
the facts are clear. In most crashes buckling up does
matter ... a lot!
Why Safety Belts Work
Q: Aren’t safety belts for kids?
A: Yes. And they’re for adult truckers, and anyone
else who rides in your vehicle.
Here’s why: when your vehicle goes, say, 30 mph
(50 km/h), so do you and your passengers.

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If the vehicle hits something, it stops -- right then. But
nothing stops the people. They keep moving. Then something will stop them. It could be the windshield.

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Or it could be the instrument panel.
Now, what if you and your passengers were to give that
big vehicle a chance to deal with the force of the impact,
instead of you?
With belts, you slow down as the vehicle does. You get
more time to stop.
You stop over more distance, and your strongest bones
take the forces. Safety belts are for everyone.

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Here Are Questions Many People Ask
About Safety Belts -- and the Answers
Q: Won’t I be trapped in the vehicle after an
accident if I’m wearing a safety belt?
A: You could be -- whether you’re wearing a safety
belt or not. But you can unbuckle a safety belt,
even if you’re upside down. And your chance of
being conscious during and after an accident, so
you can unbuckle and get out, is much greater if
you are belted.
Q: If my vehicle has air bags, why should I have to
wear safety belts?
A: Air bags are in many vehicles today and will be in
most of them in the future. But they are
supplemental systems only; so they work with
safety belts -- not instead of them. Every air bag
system ever offered for sale has required the use of
safety belts. Even if you’re in a vehicle that has air
bags, you still have to buckle up to get the most
protection. That’s true not only in frontal collisions,
but especially in side and other collisions.
Q: If I’m a good driver, and I never drive far from
home, why should I wear safety belts?
A: You may be an excellent driver, but if you’re in an
accident -- even one that isn’t your fault -- you and
your passengers can be hurt. Being a good driver
doesn’t protect you from things beyond your
control, such as bad drivers.
Most accidents occur within 25 miles (40 km)
of home. And the greatest number of serious
injuries and deaths occur at speeds of less than
40 mph (65 km/h).
Safety belts are for everyone.

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How to Wear Safety Belts Properly
Adults
This part is only for people of adult size.
Be aware that there are special things to know
about safety belts and children. And there are
different rules for smaller children and babies. If a
child will be riding in your vehicle, see the part of
this manual called “Children.” Follow those rules
for everyone’s protection.
First, you’ll want to know which restraint systems your
vehicle has.
We’ll start with the driver position.
Driver Position
This part describes the driver’s restraint system.
Lap-Shoulder Belt
The driver has a lap-shoulder belt. Here’s how to wear
it properly.
1. Close and lock the door.
2. Adjust the seat (to see how, see “Seats” in the Index)
so you can sit up straight.
3. Pick up the latch plate and pull the belt across you.
Don’t let it get twisted.
The shoulder belt may lock if you pull the belt across
you very quickly. If this happens, let the belt go back
slightly to unlock it. Then pull the belt across you
more slowly.
There is a clip on the lap portion of the lap-shoulder
belt. Make sure this clip is not too close to the latch
plate when you wear your safety belt, so you can
make the belt snug.

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4. Push the latch plate into the buckle until it clicks.
Pull up on the latch plate to make sure it is secure.
If the belt isn’t long enough, see “Safety Belt
Extender” at the end of this section.
Make sure the release button on the buckle is
positioned so you would be able to unbuckle the
safety belt quickly if you ever had to.
5. To make the lap part tight, pull down on the buckle
end of the belt as you pull up on the shoulder belt.
The lap part of the belt should be worn low and snug on
the hips, just touching the thighs. In a crash, this applies
force to the strong pelvic bones. And you’d be less likely
to slide under the lap belt. If you slid under it, the belt
would apply force at your abdomen. This could cause
serious or even fatal injuries. The shoulder belt should go
over the shoulder and across the chest. These parts of the
body are best able to take belt restraining forces.
The safety belt locks if there’s a sudden stop or a crash,
or if you pull the belt very quickly out of the retractor.

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Q: What’s wrong with this?
A: The shoulder belt is too loose. It won’t give nearly
as much protection this way.
CAUTION:
You can be seriously hurt if your shoulder belt is
too loose. In a crash, you would move forward
too much, which could increase injury. The
shoulder belt should fit against your body.

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Q: What’s wrong with this?
A: The belt is buckled in the wrong place.
CAUTION:
You can be seriously injured if your belt is
buckled in the wrong place like this. In a
crash, the belt would go up over your abdomen.
The belt forces would be there, not at the
pelvic bones. This could cause serious internal
injuries. Always buckle your belt into the buckle
nearest you.

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Q: What’s wrong with this?
A: The shoulder belt is worn under the arm. It should
be worn over the shoulder at all times.
CAUTION:
You can be seriously injured if you wear the
shoulder belt under your arm. In a crash, your
body would move too far forward, which would
increase the chance of head and neck injury.
Also, the belt would apply too much force to the
ribs, which aren’t as strong as shoulder bones.
You could also severely injure internal organs
like your liver or spleen.

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Q: What’s wrong with this?
A: The belt is twisted across the body.
CAUTION:
You can be seriously injured by a twisted belt. In
a crash, you wouldn’t have the full width of the
belt to spread impact forces. If a belt is twisted,
make it straight so it can work properly, or ask
your dealer to fix it.