1999 GMC C-SERIES fuel

yellowblue
7-13 72,000 Miles (120 000 km)

Engine oil and filter service. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(2)(6)

Chassis lubrication service (or every 6 months,
whichever occurs first). (12)

Inspect door hinge pins and bushings and replace as
necessary. Lubricate door hinge pins and rollers with
engine oil.

Replace air conditioning filter dryer (or every
18 months, whichever occurs first, and whenever
refrigerant charge is lost for any reason).

Wheel bearing (grease type) service (or every
24 months, whichever occurs first, and whenever
hubs are removed). (23)

Wheels and tires service. (15)

Hydraulic brake service (or every 6 months,
whichever occurs first). (7)

Hydraulic brake caliper service (or every 6 months,
whichever occurs first). (22)

Hydraulic parking brake service (or every 6 months,
whichever occurs first). (8)

Engine drive belts service (or every 12 months,
whichever occurs first). (18)

Clutch pedal free travel service. (10)
Throttle linkage service. (19)

Thermostatically controlled engine cooling
fan service. (4)(20)

Shields and underhood insulation service. (4)(5)(21)

Air intake system service (or every 24 months,
whichever occurs first). (4)(5)(24)

Thermostatically controlled air cleaner service (or
every 24 months, whichever occurs first). (3)(4)(25)

Fuel tank, fuel cap and fuel lines service (or every
72 months, whichever occurs first). (3)(30)

EGR system inspection (or every 72 months,
whichever occurs first). (3)(31)
Electronic Vacuum Regulator Valve (EVRV)
inspection (or every 72 months, whichever occurs
first). (3)(32)
Evaporative Control System Service (if equipped)
(or every 24 months, whichever occurs first).
(3)(26)

Rear axle air shift motor service. (11)
Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours,
whichever occurs first).
(Continued)
ProCarManuals.com

yellowblue
7-15

Hydraulic brake service (or every 6 months,
whichever occurs first). (7)

Hydraulic parking brake service (or every 6 months,
whichever occurs first). (8)

Engine drive belts service (or every 12 months,
whichever occurs first). (18)

Clutch pedal free travel service. (10)

Throttle linkage service. (19)

Thermostatically controlled engine cooling
fan service. (4)(20)

Shields and underhood insulation service. (4)(5)(21)

Check air brake relay valve operation and check for
leaks (or every month, or every 300 hours,
whichever occurs first).
87,000 Miles (145 000 km)

Engine oil and filter service. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(2)(6)
90,000 Miles (150 000 km)

Engine oil and filter service. (3)(9)

Check fluid levels (or every 3 months, whichever
occurs first). (1)(2)(6)

Chassis lubrication service (or every 6 months,
whichever occurs first). (12)
Replace fuel filter(s) (or every 12 months, whichever
occurs first). (3)

Air cleaner filter replacement service (or every
24 months, whichever occurs first). (3)(4)(27)

Steering system service. (13)

Front and rear suspension service. (14)

Spring
-to-axle U-bolts and shackle bolts service. (16)

Exhaust system service (or every 6 months,
whichever occurs first). (3)(4)(17)

Air brake service (or every 6 months, whichever
occurs first). (39)

Inspect door hinge pins and bushings and replace as
necessary. Lubricate door hinge pins and rollers with
engine oil.

Replace air conditioning filter dryer (or every
18 months, whichever occurs first, and whenever
refrigerant charge is lost for any reason).

Wheels and tires service. (15)

Hydraulic brake service (or every 6 months,
whichever occurs first). (7)

Hydraulic brake caliper service (or every 6 months,
whichever occurs first). (22)

Hydraulic parking brake service (or every 6 months,
whichever occurs first). (8)
(Continued)
ProCarManuals.com

yellowblue
7-21
(25) = Check thermostatically controlled air cleaner
installation to make certain that all ducts are connected and
correctly installed. Also, check valve for proper operation.
(26) = Evaporative Control System Service (if equipped):
Check all fuel and vapor lines and hoses for proper
connections and correct routing (or every 24 months,
whichever occurs first). Replace parts as needed.
(27) = Replace air cleaner filter (or every 24 months,
whichever occurs first). Replace filter more often if
driving in dusty conditions. Ask your dealer for the
proper replacement intervals for your driving conditions.
(28) = Replace spark plugs. Inspect wires for damage.
Check the wire boot and boot heat shield fit at spark
plugs and coil. Replace parts as needed.
(30) = Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(31) = Check EGR system as described in the service
manual. See ªService and Owner Publicationsº in the Index.
(32) = Inspect Electronic Vacuum Regulator Valve
(EVRV) filter for excessive contamination or plugging.
If needed, clean filter with solution of soap and water,
let dry and install.(33) = Check the PCV system for proper operation and
clean PCV valve. Replace hoses as needed.
(34) = Replace PCV valve and blow out the PCV valve
hose with compressed air. Replace hoses as needed.
(35) = Drain, flush and refill cooling system. See
ªRecommended Fluids and Lubricantsº in the Index for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap and neck. Pressure test cooling system and
pressure cap. For Caterpillar
 diesel engines, always refer
to the Caterpillar Diesel Engine Operation & Maintenance
Manual for coolant recommendations and change intervals.
(37) = Rear axle service: Change the lubricant. See
ªRecommended Fluids and Lubricantsº in the Index.
(38) = Front axle service: Re
-pack upper kingpin
roller bearing.
(39) = Air brake service:

Inspect brake lines and hoses for proper hook
-up,
binding, leaks, cracks, chafing, etc. Inspect drum
brake linings for wear or cracks. Inspect other brake
parts at each wheel, including drums, wheel cylinders
and piston heat shields and boots. Check brake pedal
for excessive free play or travel (or every 6 months,
whichever occurs first) and have serviced if needed.
Check brakes more often if driving habits and
conditions result in frequent braking.
ProCarManuals.com

yellowblue
7-23
Part B: Owner Checks and Services
Listed in this part are owner checks and services which
should be performed at the intervals specified to help
ensure the safety, dependability and emission control
performance of your vehicle.
For your safety and that of others, any of the
safety
-related components that may have been damaged
in an accident should be checked and any needed repairs
made before operating the vehicle.
At the minimum, these routine checks should be made
every 6 months or 6,000 miles (10 000 km), whichever
occurs first. Whenever repairs are needed, have them
completed before operating the vehicle.
At Each Fuel Fill
It is important for you or a service station attendant to
perform these underhood checks at each fuel fill.Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See ªEngine Oilº in the Index for
further details.
Engine Coolant Level Check
Check the engine coolant level and add DEX
-COOL

coolant mixture if necessary. See ªEngine Coolantº in
the Index for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid if
necessary. See ªWindshield Washer Fluidº in the Index
for further details.
Tire Inflation Check
Check tire inflation cold. Make sure tires are inflated to
the pressures specified on the Certification/Tire label.
See ªTiresº in the Index for further details.
ProCarManuals.com

yellowblue
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.
ProCarManuals.com

yellowblue
9-4
Engine (Continued)
Fuse Blocks 6-69, 6-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Identification 6-67 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil 6-13, 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Filters and PCV Valves 6-77 . . . . . . . . . . . . . . . . . . . . .
Oil Level Check 7-23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overheating 5-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Road Speed Governor 2-54 . . . . . . . . . . . . . . . . . . . . . . . . .
Running While Parked 2-30 . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Over-Crank Protection 2-7 . . . . . . . . . . . . . . . . . . . .
Starting 2-7, 2-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Oil 6-13, 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additives 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking 6-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engines 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Life Monitor 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Gage 2-66 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Used 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
What Kind to Use 6-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
When to Add 6-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
When to Change 6-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ether Injection System 6-46 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust
Brake 2
-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine 2-29, 2-30, 4-27 . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Check 7-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fabric Cleaning 6-59 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filling a Portable Fuel Container 6-8 . . . . . . . . . . . . . . . . . . . .
Filling Your Tank 6-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filter
Air Cleaner 6
-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Compressor 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Oil 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filterminder Gage 2-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Finish Care 6-63 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Finish Damage 6-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flashers, Hazard Warning 5-2 . . . . . . . . . . . . . . . . . . . . . . . . .
Flat Tire, Changing 5-34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fluid Leaks Check 7-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fluids and Lubricants 7-28 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Footnotes 7-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
French Language Manual ii. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Towing 5
-10, 5-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Wheel Bearings with Oil-Filled Hubs 6-47 . . . . . . . . . .
Fuel
Diesel Engine 6
-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filling a Portable Container 6-8 . . . . . . . . . . . . . . . . . . . . . .
Filling Your Tank 6-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filter 6-44, 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gage 2-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gasoline Engine 6-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tank Capacity 6-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Water in Fuel 6-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuels in Foreign Countries -- Gasoline 6-6 . . . . . . . . . . . . . . .
Fuses and Circuit Breakers 6-69 . . . . . . . . . . . . . . . . . . . . . . .
Fusible Links 6-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ProCarManuals.com

yellowblue
9-5
Gages
Air Pressure 2-69 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature 2-61 . . . . . . . . . . . . . . . . . . . .
Engine Oil Pressure 2-65 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filterminder 2-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel 2-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hourmeter 2-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Pressure 2-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Speedometer 2-53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tachometer 2-54 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmission Temperature 2-69 . . . . . . . . . . . . . . . . . . . . . .
Voltmeter 2-56 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Guide en Fran†ais ii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hazard Warning Flasher Switch 5-3 . . . . . . . . . . . . . . . . . . .
Hazard Warning Flashers 5-2 . . . . . . . . . . . . . . . . . . . . . . . . . .
Head Restraints 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Headlamps 2-43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High/Low Beam Changer 2-34 . . . . . . . . . . . . . . . . . . . . . .
Wiring 6-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heating 3-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Highway Hypnosis 4-21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hill and Mountain Roads 4-22 . . . . . . . . . . . . . . . . . . . . . . . . .
Hood
Access Panels 6
-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Things Under 6-9 . . . . . . . . . . . . . . . . . . . . . . . . .
Latches Check 7-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Horn 2-31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hourmeter Gage 2
-70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hydraulic Brake Warning Light 2-58 . . . . . . . . . . . . . . . . . . . .
Hydroplaning 4-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ignition Positions 2-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inflation, Tire 6-49 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspections
Engine Cover Check 7
-27 . . . . . . . . . . . . . . . . . . . . . . . . . .
Underbody 7-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instrument Panel 2-50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Breaker Block 6-69 . . . . . . . . . . . . . . . . . . . . . . . . .
Cleaning 6-61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cluster 2-52 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Intake Heater Indicator Light 2-63 . . . . . . . . . . . . . . . . . . . . . .
Inter-Axle Differential Lock Control 2-40 . . . . . . . . . . . . . . . .
Jump Starting 5-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Keys 2-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Labels
Certification/Tire 4-28, 6-67 . . . . . . . . . . . . . . . . . . . . . . . .
Service Parts Identification 6-67 . . . . . . . . . . . . . . . . . . . . .
Vehicle Identification Number 6-67 . . . . . . . . . . . . . . . . . . .
Lamp and Bulb Data 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lamp Check 7-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ProCarManuals.com