1999 GMC C-SERIES Owners Manual

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1-3 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.
Seatback Latches
The front of the full-width bench seat seatback folds
forward to let you reach the rear of the cab. Bucket seats
have outboard
-mounted levers to tilt the seatbacks
forward or rearward.
Your seatback will move back and forth freely unless
you come to a sudden stop
-- then it will lock into place.
If your vehicle is parked going down a fairly steep hill,
the seatback may not fold without some help from you.
To fold the seatback
forward, push the seatback
toward the rear of the
vehicle as you lift this latch.
The latch must be down for
the seat to work properly.
Bench Seat Shown
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.
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1-4 National Seats (If Equipped)
If your vehicle has the low-back National seat, there are
six ways you can adjust the seat.
If your vehicle has the high
-back National seat, there are
five ways you can adjust the seat.Height Adjustment
To adjust the height of a
self
-contained seat
(hand
-pumped air seat),
push the seat height
adjustment pump lever,
located on the lower
outboard side, down and
continue pumping to raise
the seat. Press the lever and
hold it to lower the seat.
To adjust the height of air
-sourced seats, use the knob
on the front left
-hand side on the seat. Push the knob to
inflate. Pull the knob to deflate.
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1-5
To adjust the height of the
cushion, lift the cushion
height adjustment handle up
and forward. You can
choose between two
settings. The handle is
located underneath the seat,
in the front.
Lumbar Adjustments
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.Seatback Adjustment
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.
Fore
-and-Aft Adjustment
To slide the seat forward or
backward, move the lever
toward the passenger's side.
The seat will lock in at
1/2 inch (1.5 cm)
increments. The lever is
located underneath the seat,
in the front.
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1-6
Chugger-Snubber Lock-Out Feature (If Equipped)
This handle is located on
the lower outboard side of
the driver's seat and the
inboard side of the
passenger's seat. Move the
handle down to isolate any
backslap experienced while
in tractor/trailer operation or
while operating a dump
truck application. This is
only available on
low
-back seats.
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.
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1-7
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.
If your vehicle has a safety
belt reminder light, a light
comes on as a reminder to
buckle up. (See ªSafety
Belt Reminder Lightº in
the Index.)If your vehicle has a safety belt reminder tone, a tone
comes on as a reminder to buckle up. See ªSafety Belt
Reminder Toneº in the Index.
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!
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1-8 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.
If the vehicle hits something, it stops -- right then. But
nothing stops the people. They keep moving.
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1-9
Then something will stop them. It could be
the windshield.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?
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1-10
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.
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.
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