1999 GMC C-SERIES key

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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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6-16 Engine Oil Additives
Don't add anything to your oil. Your dealer is ready to
advise if you think something should be added.
When to Change Engine Oil
Your vehicle has a computer that lets you know when to
change your engine oil. This is not based on mileage,
but on engine revolutions and engine operating
temperature. When the computer has calculated that the
oil needs changing, the Oil Life Monitor will indicate
that a change is necessary. The mileage between oil
changes will vary depending on how you drive your
vehicle
-- usually between 3,000 miles (5 000 km) and
7,500 miles (12 500 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your vehicle
more than 7,500 miles (12 500 km) or 12 months
(whichever occurs first) without an oil change.
The system won't detect dust in the oil. So, if you
drive in a dusty area, be sure to change your oil every
3,000 miles (5 000 km) or sooner. Remember to reset
the CHANGE OIL light whenever the oil is changed.How to Reset the Oil Life Monitor
To reset the CHANGE OIL message, turn the ignition
key to RUN with the engine off. Fully press and release
the accelerator pedal three times within 10 seconds. If
the CHANGE OIL message flashes for five seconds, the
system is reset. If the message does not display for five
seconds, you will need to reset the system again.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements that may be unhealthy for your skin and could
even cause cancer? Don't let used oil stay on your skin
for very long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer's warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free
-flowing oil
from the filter before disposal. Don't ever dispose of oil
by putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead,
recycle it by taking it to a place that collects used oil. If
you have a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center for help.
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7-20
(16) = Check spring-to-axle U-bolts and shackle bolts
for proper torque. See the service manual for torque
sequence and specifications. When parts are replaced,
the torque must be checked and adjusted more often
during the first 6,000 miles (10 000 km). Check torque
at 500 miles (800 km) and 2,000 miles (3 000 km) after
first use of parts.
(17) = Check complete exhaust system and cab areas
near the exhaust system for broken, damaged, missing or
out
-of-position parts. Also inspect for open seams,
holes, loose connections or other conditions which could
let exhaust fumes seep into the driver compartment.
Needed repairs should be made at once. To help
maintain system integrity, replace exhaust pipes
whenever a new muffler is put on.
(18) = Check all engine drive belts for cracks, fraying,
wear and proper tension. Adjust or replace as needed.
(19) = Check throttle linkage for damaged or missing
parts (including throttle return springs), interference or
binding. Fix any problems at once. Do not lubricate
accelerator and cruise control cables.
(20) = With the engine off and below normal operating
temperature, check to see that the thermostatically
controlled engine cooling fan can be rotated by hand on
viscous
-operated drives. Replace as needed.(21) = Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(22) = Lubricate caliper housing, caliper support spring
and caliper support key.
(23) = Wheel bearing service:

Grease type
-- Clean, inspect and lubricate with the
proper wheel bearing grease at designated intervals
or when hubs are removed. See ªRecommended
Fluids and Lubricantsº in the Index.

Oil
-filled type -- Some wheel bearings are lubricated
by rear axle lubricant. When you have oil
-filled
hubs, use lubricant identical to that used in your rear
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain oil
level at the OIL LEVEL mark between change
intervals. See ªRecommended Fluids and
Lubricantsº in the Index.
(24) = Check the air intake system installation to see
that gaskets are seated properly and all hose
connections, fasteners and other components are tight.
For gasoline engines, also check to be sure the air
cleaner housing is properly seated, that the cover fits
tightly and that the wing nut is tight. Tighten
connections and fasteners or replace parts as required.
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7-27
Door Latches Check
Check that doors close, latch and lock tightly. Check for
broken, damaged or missing parts that might prevent
tight latching.
Hood Latches Check
Check that the hood closes firmly. Check for broken,
damaged, loose or missing parts that might prevent tight
latching. Make sure the secondary latch (if equipped)
keeps the hood from opening all the way when the
primary latch is released.
Fluid Leaks Check
Check for fuel, coolant, oil or other fluid leaks by
looking at the surface beneath the vehicle after it has
been parked for a while.
Underbody Inspection
Corrosive materials used for ice, snow removal and dust
control can collect on the underbody. If these materials
are not removed, accelerated corrosion (rust) can occur
on underbody parts such as fuel lines, frame, floor pan
and exhaust system. At least every spring, flush these materials from the underbody with plain water. Take
care to clean well any areas where mud and other debris
can collect. Sediment packed in closed areas of the
frame should be loosened before being flushed.
Engine Cover Check
Check that the cab's engine cover and seal (if equipped)
are not torn or damaged. Be sure that the cover is bolted
down firmly to the floor.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part C.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Tractor Protection (Breakaway) Valve Check
On air brake models, remove, disassemble, clean and
inspect the tractor protection (breakaway) valve.
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7-29
USAGEFLUID/LUBRICANT
Brake Caliper
Housing, Caliper
Support Spring
and Caliper
Support KeyAeroshell #5 Grease (GM Part
No. 12377969 or equivalent).
Air Brake
System Alcohol
EvaporatorCommercial grade of Methyl
Alcohol as specified in
GM 6015
-M.
Power Steering
SystemGM Power Steering Fluid
(GM Part No. 1052884
- 1 pint,
1050017
- 1 quart, or equivalent).
Manual
TransmissionSynthetic Manual Transmission
Fluid (GM Part No. 12345724) is
the recommended lubricant to use.
USAGEFLUID/LUBRICANT
Automatic
TransmissionSee the Allison Transmission
Operator's Manual for correct
Transmission Fluid.
Chassis
LubricationChassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
Wheel Bearing
GreaseWheel Bearing Lubricant meeting
requirements of NLGI # 2,
Category GC or GC
-LB (GM
Part No. 1051344 or equivalent).
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8-5
Roadside Assistance
GM Medium Duty Truck's Roadside Assistance
provides stranded owners with towing service for
disabled vehicles.This service combines the efforts of trained telephone
representatives with a network of GM Medium Duty
Truck's dealer services.
Just dial Medium Duty Roadside Assistance at
1
-800-GMC-8782 (1-800-462-8782) to reach a
qualified representative who can assist you in a repair
or arrange a tow. Other recommended services can
also be arranged for situations such as retrieving
locked
-in keys, changing a tire or delivering gasoline,
at a charge to the owner. We also provide dealer
information at no charge such as location of the nearest
authorized medium duty GM Truck dealer and their
hours of operation.
Roadside Assistance is available 24 hours a day, 7 days
a week, 365 days a year, including weekends and
holidays. Should you have any questions about Roadside
Assistance, call the GMC Roadside Assistance Center or
contact your dealer.
Warranty Information
Your vehicle comes with a separate warranty booklet
that contains detailed warranty information.
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