1999 GMC C-SERIES Owners Manual

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4-29
The Certification/Tire label is provided by the final
manufacturer and should be on the door or door jamb. It
also tells you the maximum weights for the front and rear
axles, called Gross Axle Weight Rating (GAWR). To find
out the actual loads on your front and rear axles, you
need to go to a weigh station and weigh your vehicle.
Your dealer can help you with this. Be sure to spread out
your load equally on both sides of the centerline.
Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
And, if you do have a heavy load, you should spread
it out.
CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose control
and crash. Also, overloading can shorten the life
of your vehicle.
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Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load your vehicle the right way.
NOTICE:
Your warranty does not cover parts or
components that fail because of overloading.
If you put things inside your vehicle -- like suitcases,
tools, packages or anything else
-- they will go as fast as
the vehicle goes. If you have to stop or turn quickly, or
if there is a crash, they'll keep going.
CAUTION:
Things you put inside your vehicle can strike and
injure people in a sudden stop or turn, or in
a crash.

Put things in the cargo area of your vehicle.
Try to spread the weight evenly.

Never stack heavier things, like suitcases,
inside the vehicle so that some of them are
above the tops of the seats.

Don't leave an unsecured child restraint in
your vehicle.

When you carry something inside the
vehicle, secure it whenever you can.
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Power Take-Off (PTO) (If Equipped)
Before using a PTO, refer to the body builder's or
operator's instructions.
To engage a PTO:
1. Make sure the vehicle is stopped.
2. Shift the transmission into NEUTRAL (N) or
PARK (P), if equipped.
3. The brake or clutch pedal must be pressed and
released once before PTO can be enabled. Do not
hold the brake or clutch pedal down.4. The cruise control switch must be in ON prior to
engaging the PTO switch to enable PTO operation.
This sets the PTO base engine idle at 1200 rpm.
5. Use SET/COAST to change the engine speed to the
lower preset value of 1400 rpm. Use
RESUME/ACCEL to change the engine speed to the
upper preset value of 1800 rpm. You may toggle
between upper and lower by moving the switch
between SET/COAST and RESUME/ACCEL.
The PTO will become inoperative when any of the
conditions are changed or the CHECK GAGES light
comes on.
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4-32
-NOTES
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5-
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5-1
Section 5 Problems on the Road
Here you'll find what to do about some problems that can occur on the road.
5
-2 Hazard Warning Flashers
5
-3 Other Warning Devices
5
-5 Jump Starting
5
-9 Towing Your Vehicle
5
-18 Engine Overheating
5
-20 Cooling System (Gasoline Engine)5
-27 Cooling System (Diesel Engine)
5
-33 Engine Fan Noise
5
-34 If a Tire Goes Flat
5
-34 Changing a Flat Tire
5
-37 If You're Stuck: In Sand, Mud, Ice or Snow
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5-2
Hazard Warning Flashers
Your hazard warning flashers let you warn others. They
also let police know you have a problem. Your front and
rear turn signal lamps will flash on and off.
The hazard flasher switch is located on the
steering column.
Press the button in to make your front and rear turn
signal lamps flash on and off.
Your hazard warning flashers work no matter what
position your key is in, and even if the key isn't in.
To turn off the flashers, pull out on the collar. When
the hazard warning flashers are on, your turn signals
won't work.
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5-3 Hazard Warning Flasher Switch
(If Equipped)
With some options, such as U86-trailer wiring or
RQ3
-tractor application, you will have this switch.
This switch replaces the hazard switch mounted on the
steering column. It is mounted in the instrument panel,
usually to the left of and below the steering column.
Pull the switch out to make your front and rear turn
signal lamps flash on and off. A light next to the switch
will also flash. Push it back in to turn off the flashers.
The turn signal lamps won't flash if you're braking.
This switch works no matter what position the key is in,
and even if the key isn't in the ignition.
When the hazard warning flashers are on, your turn
signals won't work.
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5-4 Signal-Stat Turn Signal and Hazard
Warning Flasher (If Equipped)
If you have this system, it lets you warn others. It also
lets police know you have a problem. It makes your
front and rear turn signal lamps flash on and off, but
they won't flash if you're braking.
The switch is on the end of the signal
-stat housing.
To make it work, pull out on the hazard lever until it
locks into place. It works no matter what position your
key is in, and even if the key isn't in.
To turn off the flasher, move
the turn signal lever either
up or down. Then move the
signal lever back to the
center position.
When the hazard warning flashers are on, your turn
signals won't work.
Other Warning Devices
If you carry reflective triangles, you can set one up at
the side of the road behind your vehicle in the
recommended manner per FMCSR (Federal Motor
Carrier Safety Regulation) Section 392.22, to
warn others.
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