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Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your GM dealer before adding equipment to the outside
of your vehicle.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System” in the Diesel Engine
Supplement. For vehicles with gasoline engines, please
read this.
Use regular unleaded gasoline rated at 87 octane or
higher. At a minimum, it should meet specifications
ASTM D4814 in the United States and CGSB 3.5-M93
in Canada. Improved gasoline specifications have been
developed by the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting
the AAMA
specification could provide improved driveability and
emission control system protection compared to
other gasolines. Be
sure the posted octane is
at least 87. If the octane is
less than 87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a hill. That’s normal,
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood tune-up label),
it is designed to operate on fuels that meet California
specifications. If such fuels are not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp on
your instrument panel may turn on and/or your vehicle
may fail a smog-check test. If this occurs, return to your
authorized GM dealer for diagnosis to determine the
cause
of failure. In the event it is determined that the
cause of the condition is the type of fuels used, repairs
may not be covered by your warranty.
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When you put the cap back on, turn it to the right
(clockwise) until
you hear a clicking sound. Make sure
you fully install the cap.
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
1
To open the hood, first
pull this handle inside the
vehicle. It is just in front of
the driver’s side
door frame
near the floor.
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Inflation -- Tire Pressure
The Certificationmire label, which is on the rear edge of
the driver’s door, 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
1 mile (1.6 km).
NOTICE:
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:
@ Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
I
When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure
to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
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Engine Identification -- Gasoline Engines
Engine “VORTEC”4300 “VORTEC”5000
Type V6 V8
VIN Code
w M
Fuel System CSFI’ CSFI*
]Central
Sequential Fuel Injection
2Sequential Fuel Injection
Wheel Nut Torque
MODEL TORQUE
All 140 ft-lb (190 N-m)
Cooling System Capacity
ENGINE VIN
“VORTEC”4300
“VORTEC”5000
“VORTEC”5700
“VORTEC”7400 W
M
R
J
QTJ “VORTEC”5700
V8
R
CSFI’
1 Without Rear Heater*
11
Quarts (10.4 L)
17 Quarts (16 L)
17 Quarts (16 L)
23 Quarts (2 1.8 L)
“VORTEC”7400
V8
J
SF12
rl With Rear Heater 8
14 Quarts (13.2 L)
20 Quarts (18.9 L)
20 Quarts (18.9 L)
26 Quarts (24.6 L)
After refill, the level MUST be checked as outlined under “Engine Cooling System” in Section 5.
*All quantities are approximate.
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Crankcase Capacity
ENGINE VIN Quantity With Filter
“VORTEC”4300 W 4.5 Quarts (4.3 L)
“VORTEC”5000
“VORTEC”5700
“VORTEC”7400 M
R
J
5 Quarts (4.8 L)
5 Quarts (4.8 L)
7 Quarts (6.5 L)
Fuel Tank Capacity
TYPE QUANTITY
Standard Tank 3 1 Gallons (1 17.33 L)
Optional Tank* * 55 Gallons (208.18 L)
*All quantities are approximate.
** 159’’ , 177” Wheelbase Vehicles Only.
All quantities are approximate. After refill, the level MUST be checked as outlined
under “Engine Oil And Filter Recommendations’’ in
Section
5.
**Add one additional quart for RPO 5Z1 and
WO KL5 Models.
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Normal Replacement Parts
Engine “VORTEC”4300 “VORTEC”5000 “VORTEC”5700 “VORTEC”\
7400
VIN w M R J
Oil Filter PF52 PF1218 PF1218 PF1218
Air Cleaner Filter* A917C A917C A917C A917C
PCV Valve CV789C cv774c cv774c cv774c
Spark Plugs 41-932 4 1-932 41-932 4 1-932
Fuel Filter GF48
1 GF48 1 GF48 1 GF48 1
Radiator Cap RC36 RC36 RC36 RC36
*Replace with
AC Air Filter, Part No. A917C and for severe dusty conditions, use, AC Air Filter, Part No. 1236C.
Air Conditioning Refrigerant Capacity
I NOTICE:
~~
R-134A refrigerant is not compatible with R-12
refrigerant in an air conditioning system. R-12 in
an R-134A system
will cause compressor failure,
refrigerant oil sludge,
or poor air conditioning
system performance. TYPE
QTY Front Only QTY Front and Rear
Refrigerant 3.00 lbs. (1.36 kg) 4.875 lbs. (2.21 kg)
R- 134A
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.
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