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Be careful not to spill gasoline. Clean gasoline from
painted surfxes as soon
as possible. See “Cleaning the
Outside
of Your Vehicle” in the Index.
When you put the cap back
on, turn it to the right until
you hear at least three clicks. Make sure you fully install
the cap. The diagnostic system can determine if the fuel
cap has been
left off or improperly installed. This would
allow
fuel to evaporate into the atmosphere. See
“Malfunction Indicator Lamp” in the Index.
I NOTICE:
If you need a new cap, be sure to get the right
type. Your dealer can get one for you. If you get
the wrong type, it may not fit or have proper
venting, and your fuel tank and emissions system
might be damaged.
Checking Things Under the Hood
h
I ! CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
hjure you even when the engine
is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline or
diesel fuel, oil, coolant, brake fluid, windshield
washer and other fluids, and plastic or rubber.
You
or others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
6-6
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Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine Oil
(Diesel Engine)” in the Diesel Engine Supplement.
It’s a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the
oil must
be warm and the vehicle must
be on level ground. Turn
off the
engine and give the oil a few minutes to
drain back into the oil pan.
If you don’t, the oil dipstick
might not.show the actual level.
Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then
push it back in all the way. Remove it again,
keeping the tip down, and check the level.
The engine oil dipstick has a yellow ring handle and is
located on the passenger side
of the engine.
6-12
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What Kind of Oil to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that the
oil has been certified by the American
Petroleum Institute
(API). Do not use any oil which
does not carry this Starburst symbol.
If you change your own oil,
be sure you use oil that has
the Starburst symbol on the
front of
the oil container.
If you have your oil changed for you, be sure the oil put
into your engine is American Petroleum Institute
certified for gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown
in the following chart:
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS ~~ . . - . . -.
FOR BEST FUEL E Y AND COLD STARTING, SELECT THE LOWEST
~ ~~~ ~ ~
SAE VISCOSITY Gnnvr ulL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
C
I +3*
+ 27
i SAE SW-30
’I PREFERRED
LOOK
FOR THIS
SYMBOL
COLD
WEATHER
DO NOT USE SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED
6-14
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Page 299 of 404

Inflation -- Tire Pressure
The Certification/Tire label. which is on the rear edge of
the driver's door, or on the incomplete vehicle document
in the cab, shows the correct inflation pressures for your
tires when they're cold. "Cold" means your vehicle has
been sitting for at least three hours or driven no more
than
I mile (I .6 km).
You can operate some vehicles at reduced inflation
pressures
only when you'll be carrying reduced loads.
On those vehicles, the minimum cold inflation pressures
for a typical reduced load are printed on the Improved
Ride Tire Pressure label located
on the driver's door.
Weigh the vehicle to find the load on each tire and see
the label for the
minimum cold inflation pressures for
that load.
1 NOTICE:
~.
1
Don't let anyone tell you that underinflation or
overinflation is
all right. It's not. If your tires
don't have enough air (underinflation), you can
get the following:
NOTICE: (Continued)
NOTICE: (Continued)
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
if your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When
to Check
Check your tires once
a month or more. Also, check the
tire pressure of the spare tire,
6-49
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Page 315 of 404

Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect
on the underbody, If these are
not removed, accelerated corrosion (rust) can occur
on the underbody parts such as fuel lines, frame,
floor pan and exhaust system even though they have
corrosion protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed
in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody vehicle washing system
can do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can
fdl upon and
attack painted surfxes
on your vehicle. This damage can
take two forms: blotchy, ringlet-shaped discolorations, and
small irregular dark spots etched into the paint surface.
Although
no defect in the paint job causes this, GM
will repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
This applies
only to materials manufactured and sold by
General Motors. Bodies, body conversions or equipment
not made or
sold by General Motors are not covered.
6-65
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Page 322 of 404
Fuse
ECM-B
Usage
Fuel Pump, PCM/VCM
RR DEFOG Rear Window Defogger
IGN-E Auxiliary Fan Relay Coil, A/C
Compressor Relay, Hot Fuel Module,
Dual Tanks
FUEL SOL Fuel Solenoid (Diesel Engine)
Fuse
GLOW
PLUG
HORN
AUX FAN
ECM-
1
A/C
ENG-
1
Usage
Glow plugs (Diesel Engine)
Horn, Underhood Lamps Auxiliary Fan
Injectors, PCM/VCM
Air Conditioning
Ignition Switch, EGR, Canister Purge,
EVRV Idle Coast Solenoid, Heated
02,
Fuel Heater (Diesel Engine), Water
Sensor (Diesel Engine)
LIGHTING Headlamp and Panel Dimmer Switch,
Fog and Courtesy Fuses
Battery,
Fuse Block Busbar
BATT
IGN-A
IGN-B
ABS Ignition Switch
Ignition Switch
Anti-Lock Brake Module
BLOWER
Hi Blower Relay
STOP/HAZ Stoplamps
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Page 325 of 404

Wheels and Tires
Model Torque
C 1500, K 1500, C/K 2500, C/K 3500 (Single Rear Wheels) ............................ 140 Ib-ft (190 N-m)
C3500 (Dual
Rear Wheels) ...................................................... 140 Ib-ft (190 N-m)
Tire Pressure ........................... See the Certificationflire label on the rear edge of the driver's door
or the incomplete vehicle document in the cab.
C-3500HD
.................................................................. 175Ib-ft(240N-m)
Normal Maintenance Replacement Parts
Replacement part numbers listed in this section
are based on the latest information available at the time of printing,
and are subject to change.
If a part listed in this manual is not the same as the part used in your vehicle when it was
built, or
if you have any questions, please contact your GM truck dealer.
These specifications are
for information only. If you have any questions. see the service manual for the chassis or
refer
to the body manufacturer's publications.
VIN Code w M
Oil Filter PF52
PF1218T
Air
Cleaner Filter A 1300C A 1300C
PCV Valve CV746C CV796C
Spark Plugs 4 1-932 4 1-932
Fuel Filter GF626
GF626
Wiper Blades 22 154886 221 54886
Type Trico Trico
Length
18 inches (45.0 cm) 18 inches (45.0 cm)
?Use a PF52 oil filter if your vehicle has four-wheel drive.
R
PF1218T
A 130OC
CV796C
4 1-932
GF626
22 154886
Trico
18 inches (45.0 cm)
J
PF1218
A
1300C
cv774c
41 -932
GF626
22 154886
Trico
18 inches (45.0 cm)
6-75
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J 28.5 quarts (27 L)
Fuel Tank Capacity (Approximate)
Type Quantity
Short Bed .................... .26 gallons (98 L)
Long Bed ................... .34 gallons (128 L)
Standard Crew Cab ........... 34 gallons (128 L)
Chassis-Cab Side Tank . .I ........ 23 gallons (87 L)
Chassis-Cab Rear Tank .......... 17 gallons (64 L)
3500 HD Models Side Tank ....... 23 gallons (87 L)
3500 HD Models Rear Tank ....... 18 to 20 gallons
(68 to.76
L)
-Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the air conditioning system in your vehicle needs
refrigerant, be sure the proper refrigerant is used.
If you’re not sure, ask your
GM dealer.
See the refrigerant charge label under the hood for
information regarding refrigerant capacity.
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