GMC Sierra 1999 User manual

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The 1999 GMC Sierra Owner’s Manual
1-1 Seats and Restraint Systems
This section tells you how to use your seats and safety belts properly. It also explains the air bag system.
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 8-10.
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,
the GMC Emblem and the name SIERRA 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 GMC
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
X9915 B 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.

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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.”
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 covers these models:
Regular Cab Pickup
Extended Cab Pickup
Chassis Cab

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 air bags and safety belts.
1-2 Seats and Seat Controls
1-12 Safety Belts: They’re for Everyone
1-16 Here Are Questions Many People Ask
About Safety Belts -- and the Answers
1-17 How to Wear Safety Belts Properly
1-18 Driver Position
1-24 Safety Belt Use During Pregnancy
1-25 Right Front Passenger Position
1-25 Air Bag System
1-36 Center Passenger Position
1-37 Rear Seat Passengers
1-41 Rear Safety Belt Comfort Guides for
Children and Small Adults
1-43 Children
1-46 Child Restraints
1-63 Larger Children
1-66 Safety Belt Extender
1-66 Checking Your Restraint Systems
1-66 Replacing Restraint System Parts
After a Crash

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1-2
Seats and Seat Controls
This section tells you about the seats -- how to adjust
them, and fold them up and down. It also tells you about
reclining front seatbacks and head restraints.
Manual Front Seat
CAUTION:
You can lose control of the vehicle if you try to
adjust a manual driver’s 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.
If your vehicle has a manual bucket or split bench seat,
you can adjust it with this lever located at the front of
the seat.
Lift the lever at the front of the seat to unlock it. Using
your body, slide the seat to where you want it. Then,
release the lever and try to move the seat with your body
in order to make sure the seat is locked into place.

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1-3
Cushion Tilt (If Equipped)
If your vehicle has this feature, you can raise or lower
the front of the driver’s or passenger’s seat with this
lever located at the inside edge of the seat. To raise or
lower the front of the seat, move the lever up or down in
a continuous motion until the cushion reaches the
desired height.
Manual Lumbar Control (If Equipped)
If your vehicle has a lumbar
adjustment, you can
increase or decrease lumbar
support in an area of the
lower seatback.
To increase support, turn the knob towards the front of
the vehicle.
To decrease support, turn the knob towards the rear of
the vehicle.

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Power Seat(s) (If Equipped)
Horizontal Control: If your vehicle has a power seat,
you can adjust it with this control located at the outside
edge of the seat.
Raise the front of the seat cushion by raising the forward
edge of the button. Lower the front of the seat cushion
by lowering the forward edge of the button. Move the
seat forward by moving the whole button toward the
front of the vehicle.
Raise the rear of the seat cushion by raising the rear
edge of the button. Lower the rear of the seat cushion by
lowering the rear edge of the button. Move the seat
rearward by moving the whole button toward the rear of
the vehicle.
Moving the whole button up or down raises or lowers
the entire seat cushion.
Vertical Control: If your vehicle has the power
reclining seats, you can use this button to adjust the
angle of the seatback. Move the reclining front seatback
rearward by moving the button toward the rear of the
vehicle. Move the seatback forward by moving the
button toward the front of the vehicle. See “Reclining
Seatbacks” in the Index for further information.

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Power Lumbar Control (If Equipped)
If you have power lumbar
adjustment, you can
increase or decrease lumbar
support in an area of the
lower seatback.
To increase support, press and hold the front of the
rocker switch. Let go of the switch when the lower
seatback reaches the desired level of support.
To decrease support, press and hold the rear of the
rocker switch. Let go of the switch when the lower
seatback reaches the desired level of support.
You can also reshape the back wing area of the
lower seatback.
To increase support, press and hold the top of the rocker
switch. Let go of the switch when the lower seatback
reaches the desired level of support.
To decrease support, press and hold the bottom of the
rocker switch. Let go of the switch when the lower
seatback reaches the desired level of support.

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Memory Seat (If Equipped)
The memory function
controls the driver’s
seat cushion and
recliner positions.
It does not store the lumbar or back support positions.
To set your memory seat:
1. Adjust the driver’s seat to your desired position.
2. Press the SET button and then press the 1 or 2 button
of the memory control within five seconds.
When your vehicle is in PARK (P), press the 1 or 2 side
of the memory control to recall the seat setting.
To do the same thing for a second driver, follow the
preceding steps, but press the other number of the
memory control.

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Heated Front Seats (If Equipped)
If your vehicle has heated
front seats, the ignition must
be in RUN for them
to operate.
The control for the driver’s side heated seat is located on
the driver’s side door panel. The control for the
passenger’s side heated seat is located on the
passenger’s side door panel.
To activate the heated seats, press the button once for
the HI heat setting. Press the button again for the LO
heat setting. To turn off the heated seats, press the button
a third time. An indicator light on the control will
illuminate for each heat setting anytime the heated seats
are operating.
Reclining Seatbacks
To adjust the front seatback, lift the lever upward.
Release the lever to lock the seatback where you want it.
Lift the lever again upward and the seatback will go to
an upright position.
If your vehicle has power seats with a power recliner,
see “Power Seats” in the Index for further information
on how to operate the reclining seatback feature.

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But don’t have a seatback reclined if your vehicle
is moving.
CAUTION:
Sitting in a reclined position when your vehicle is
in motion can be dangerous. Even if you buckle
up, your safety belts can’t do their job when
you’re reclined like this.
The shoulder belt can’t do its job. In a crash, you
could go into it, receiving neck or other injuries.
The lap belt can’t do its job either. In a crash the
belt could go up over your abdomen. The belt
forces would be there, not at your pelvic bones.
This could cause serious internal injuries.
For proper protection when the vehicle is in
motion, have the seatback upright. Then sit
well back in the seat and wear your safety
belt properly.

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Head Restraints
Slide the 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.
On some models, the head restraints tilt forward and
rearward also.
To tilt the head restraints forward, grasp the top of the
restraint and move it forward to where you want it to go
until you hear a click. It will then be locked into that
position until you need to move it again. Pulling it
forward past the last position will allow the restraint to
return to its upright position.
Seatback Latches
CAUTION:
If the seatback isn’t locked, it could move
forward in a sudden stop or crash. That could
cause injury to the person sitting there. Always
press rearward on the seatback to be sure it
is locked.
The seatbacks fold forward to let you access the rear of
the cab.
To fold a front seatback
forward, pull this lever
forward and fold the
seatback forward.
To return the seatback to the upright position, just push
the seatback rearward until it latches. After returning the
seatback to its upright position, pull the seatback
forward to make sure it is locked.

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Easy Entry Seat (Extended Cab Only)
CAUTION:
If any easy entry seat isn’t locked, it can move. In
a sudden stop or crash, the person sitting there
could be injured. And, even if there is no crash or
sudden stop, a driver sitting in an unlocked easy
entry seat could be startled by the sudden
movement and hit the wrong control or pedal,
causing an accident. After you’ve used it, be sure
to push rearward on any easy entry seat to be
sure it is locked.
The manual driver side front bucket seat and the manual
driver side split bench seat of your vehicle have an easy
entry feature. This makes it easy to get in and out of the
rear seat.
To operate the seat, pull
forward on the top of this
lever and tilt the seatback
forward toward the front of
the vehicle.
When you do, the seat bottom will release. Just pull or
push the seat forward until it stops.
To return the seat to its regular position, return the
seatback to its upright position, then push the whole seat
rearward until it latches.
After returning the seat to its regular position, try to
move the seat with your body in order to make sure the
seat is locked into place.

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Rear Seat (Extended Cab)
Folding the Rear Seat
The extended cab’s rear seat can be folded up to provide
more cargo space. To fold the seat:
1. Pull forward on the
release strap under the
rear seat cushion, on the
passenger’s side.
2. Fold the seat cushion upward until it latches with
the seatback.
3. Push and pull on the seat
to make sure the seat
is secure.
The extended cab’s rear seat can also be folded open for
more seating space. To use the seat:
1. Push rearward on the seat cushion while pulling up
on the release strap under the seat cushion, located
on the passenger’s side of the rear seat. Pull the seat
cushion downward until it latches.
2. After pushing the seat cushion downward, pull up on
the seat cushion to make sure it is locked.

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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.
And it explains the air bag system.
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.)
In most states and Canadian provinces, the law says to
wear safety belts. Here’s why: They work.

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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
When you ride in or on anything, you go as fast as
it goes.
Take the simplest vehicle. Suppose it’s just a seat
on wheels.

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Put someone on it. Get it up to speed. Then stop the vehicle. The rider
doesn’t stop.