height GMC C-SERIES 1999 Owners Manual

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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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1-28
A forward-facing child restraint (C-E) positions a
child upright to face forward in the vehicle.
These forward
-facing restraints are designed
to help protect children who are from 20 to 40 lbs.
(9 to 18 kg) and about 26 to 40 inches (66 to
102 cm) in height, or up to around four years of
age. One type, a convertible restraint, is designed to
be used either as a rear
-facing infant seat or a
forward
-facing child seat.
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2-19 Air Shift Control
(Manual Transmissions Only)
The lever for the rear axle
shift control is either at the
lower right corner of the
instrument panel or on the
shift lever.
When the lever is moved to HI, the rear axle will be in
the high range. Switch it to LOW to get the low range.
The two
-speed axle should be in LOW when you park
the vehicle.
You'll need to engage the transmission, even moving the
vehicle a little, to be sure the axle is in the low range.
Then apply the parking brake, shift into NEUTRAL and
shut off the engine.Also, always start the vehicle in motion with the
two
-speed axle in the LOW position. When you upshift
the rear axle from LOW to HI, move the lever to the
HI position, disengage the clutch, pause, engage the
clutch and then press down on the accelerator. When
you shift the axle down from HI to LOW, you don't
have to clutch. Just move the lever to LOW, release the
accelerator and then quickly press it down again.
Air Suspension (If Equipped)
Your vehicle may be equipped with the Hendrickson
HAS Series single
-axle air suspension which is designed
for single
-axle on-highway use. This feature is available
in the 19,000 lb. capacity and as a low profile option for
operations which require extra cubic capacity and a
reduced deck height.
With this air suspension system, the ride height is set
during vehicle assembly so that the vehicle has a constant
frame height. The system will then increase or decrease
air pressure in the air springs to maintain this height.
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2-20
Air Suspension Dump Control (If Equipped)
If your vehicle is equipped with the Hendrickson HAS
Series single
-axle air suspension, you may have this
control. The air suspension dump control allows the
operator to lower the deck height approximately
4.5 inches (11.5 cm) from the normal frame height.
The switch to deflate and
inflate the air suspension is
located on the upper left
side of the instrument panel
above the driver's side vent.
The light in the switch will be illuminated whenever the
switch is in the ªdumpedº position.
Automatic Transmission Operation
We build vehicles with four, five and six-speed
automatic transmissions. This part of the manual covers
the basics of these. With some of the transmissions, you
will find another manual in your vehicle that goes into
more detail. On the ceiling, in front of and above the
driver, or in some other place near the driver, you will
see a label that describes important operating facts about
the automatic transmission in your vehicle. Make sure
you follow the instructions on this label.
You may have a PARK (P) position for your shift lever.
This position locks your rear wheels. It is the best
position to use when you start your engine because your
vehicle can't move easily.
All vehicles equipped with automatic transmissions
can be started in PARK (P), if equipped, or in
NEUTRAL (N). When you shift out of NEUTRAL (N),
you may have to hold in a push button on the shift lever
or lift up on a release handle as you shift. See the
Allison Automatic Transmission Operator's Manual in
your vehicle for more information about this.
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5-11
Towing the Vehicle with the Front Bumper Removed
1. Remove the front bumper.
2. Connect and lock the lift chains to the front axle,
outside of the spring anchor plates as shown.
A. Spring Anchor Plate
B. Lift Chain
C. Front Axle
3. Place a 6, x 6, x 5
hardwood beam underneath and
slightly behind the front spring shackle brackets.4. Connect lift chains to the tow bar and raise the tow
bar until lift chain slack has been taken up and the
hardwood beam is fully seated against the spring
shackle brackets as shown.A. Shackle Bracket
B. Tow Bar
C. Lift Chain
D. Hardwood Beam
5. Raise the vehicle to the required height.
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5-13
A. Hardwood Board
B. Swing Arm
5. Raise the vehicle to the required height.Single Drive Rear Axle
Disconnect the propshaft at the rear axle. Secure the
propshaft to the frame or crossmember.
Tandem Drive Rear Axles
-- Forward Axle Off
the Ground
Raise the front of the vehicle until the forward
tandem axle wheels are off the ground. Remove the
rearward propshaft.
Tandem Drive Rear Axle
-- Both Axles on the
Ground Due to Type of Suspension or Attached Load
Disconnect the propshaft at the forward tandem axle.
Secure the propshaft to the frame or crossmember.
If there is damage or suspected damage to the axle(s),
remove all axle shafts. Cover the hub openings to
prevent the loss of lubricant or entry of dirt or
foreign objects.
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6-33 Four-Wheel and Six-Wheel Drum Brakes
(Air Only)
The brake drums should be removed and inspected each
time the tires are removed for rotation or changing.
When you have the front brakes replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your brakes adjust
for wear.
Air Brake Systems (If Equipped)
If you have air brakes, it is important to get rid of
moisture in the system. Moisture will damage your
system if it isn't removed daily.There are two ways to do this. One is automatic if your
air
-brake vehicle has the optional moisture ejector. If
your vehicle doesn't have that option, however, you
must drain the air reservoirs every day.
Drain them at full system
pressure. To be sure you're
at full pressure, check
your air pressure gage.
It should read at least
100 psi (692 kPa).
Moisture Ejector (Option)
If you have air brakes with a moisture ejector, the valve
automatically ejects moisture from the reserve tank
when the air compressor cycles.
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6-58
CAUTION:
Without the correct wheel, you may not be able
to stop properly, and you could have other
problems like a tire air
-out. You could have a
collision. If you don't go to your dealer to get a
new wheel, be sure you get the correct one. Each
new wheel should match the original wheel in
load
-carrying capacity, inflation pressure
capacity, diameter, width, offset and mounting
configuration.
Using wheels and tires with higher load-carrying limits
than the original wheels and tires doesn't change the
GAWR or the GVWR of your vehicle.
NOTICE:
The wrong wheel can cause trouble in bearing
life, brake cooling, speedometer/odometer
calibration, headlamp aim, bumper height,
vehicle ground clearance, stopping distance and
tire clearance to the body and chassis. You could
also have other problems like a tire air
-out.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how many miles it's been driven. It could fail
suddenly and cause an accident. If you have to
replace a wheel, use a new GM original
equipment wheel.
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9-8
Safety Belts 1-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adults 1-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Care 6-61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Center Passenger Position 1-22 . . . . . . . . . . . . . . . . . . . . . .
Children 1-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driver Position 1-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Extender 1-36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How to Wear Properly 1-11 . . . . . . . . . . . . . . . . . . . . . . . . .
Lap Belt 1-22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lap-Shoulder Belt 1-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Larger Children 1-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Questions and Answers 1-10 . . . . . . . . . . . . . . . . . . . . . . . .
Reminder Light 1-7, 2-55 . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing After a Crash 1-36 . . . . . . . . . . . . . . . . . . . . . . . .
Right Passenger Position 1-21 . . . . . . . . . . . . . . . . . . . . . . .
Smaller Children and Babies 1-23 . . . . . . . . . . . . . . . . . . . .
Use During Pregnancy 1-21 . . . . . . . . . . . . . . . . . . . . . . . . .
Why They Work 1-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety Defects, Reporting 8-6, 8-7 . . . . . . . . . . . . . . . . . . . . .
Safety Warnings and Symbols iii. . . . . . . . . . . . . . . . . . . . . . .
Scheduled Maintenance 7
-5 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Scheduled Maintenance Services 7-4 . . . . . . . . . . . . . . . . . . . .
Seat Adjuster Check 7-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seatback Latches 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seats
Bucket and Bench 1
-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chugger-Snubber Lock-Out 1-6 . . . . . . . . . . . . . . . . . . . . .
Controls 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cushion Adjustment 1-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fore-and-Aft Adjustment 1-5 . . . . . . . . . . . . . . . . . . . . . . . Height Adjustment 1
-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lumbar Adjustments 1-5 . . . . . . . . . . . . . . . . . . . . . . . . . . .
National 1-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Securing a Child Restraint 1-31 . . . . . . . . . . . . . . . . . . . . . . . .
Service 6-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bulletins, Ordering 8-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manuals, Ordering 8-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Park Brake Warning Light 2-60 . . . . . . . . . . . . . . . . . . . . . .
Parts Identification Label 6-67 . . . . . . . . . . . . . . . . . . . . . . .
Publications, Ordering 8-8 . . . . . . . . . . . . . . . . . . . . . . . . . .
Trans Filter Indicator Light 2-64 . . . . . . . . . . . . . . . . . . . . .
Work, Doing Your Own 6-3 . . . . . . . . . . . . . . . . . . . . . . . . .
Service and Appearance Care 6-1 . . . . . . . . . . . . . . . . . . . . . .
Service and Owner Publications 8-8 . . . . . . . . . . . . . . . . . . . .
Sheet Metal Damage 6-64 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Signal-Stat Turn Signal 2-33, 5-4 . . . . . . . . . . . . . . . . . . . . . .
Skidding 4-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications, Engine 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Speedometer 2-53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Switch Check 7-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starting Your Diesel Engine 2-10 . . . . . . . . . . . . . . . . . . . . . . .
Starting Your Gasoline Engine 2-7 . . . . . . . . . . . . . . . . . . . . . .
Steam 5-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steering 4-9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Check 7-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In Emergencies 4-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power 4-9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tips 4-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wheel, Tilt 2-31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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