fuel GMC SIERRA 1995 Service Manual

HEAVY DUTY EMISSIONS - GASOLINE ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS ~ ~ ~~~
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT
THE LOWEST
SAE
VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
SA€ 5W-30
LOOK
FOR THIS
SYMBOL
SAE 10W-30
PREFERRED
above 0°F (‘1 8°C)
COLD
WEATHER
00 NOT USE SA€ 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 10W-30 is best for your vehicle. However, you
can use SAE SW-30 if it’s going to be colder than 60°F (16°C) before your
next oil change. When it‘s very cold, you should use SAE 5W-30. These
numbers on
an oil container show its viscosity, or thickness. Do not use
other viscosity
oils, such as SAE 2OW-50.
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Engine Coolant Heater
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (-1 8OC) or colder. If your vehicle has this option,
see “Engine Coolant Heater’’ in the Index.
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.
Engine Oil (Diesel Engines)
It’s a good idea to check your engine oil level 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.
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Windshield Wiper Blade Inserts
To replace the
windshield wiper
blade insert, lift
the
wiper arm and rotate
the blade until
it is
facing away from the
windshield.
Unlatch the end
of the insert from the holding clips. Remove the insert and
slide
a new one in place. Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditioning
system to be sure it
has not lost any cooling ability. If you think the system
is not working properly, have your dealership check it out as soon as
possi bleb
The air conditioning will
not work when the temperature is below 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the surface under the
vehicle for water, oil, fuel
or other fluids. Water dripping from the air
conditioning system after it has been used is normal.
If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lock Cylinders
To be sure your locks operate properly, they must be lubricated. Your
vehicle’s maintenance schedule will tell you how often to lubricate them.
See “Recommended Fluids and Lubricants” in the Index for
the proper
lubricant to use.
You should
not use penetrating oils because they could wash out the factory
installed lubricant and cause
the lock to bind. De-icers which contain
alcohol could also
wash away the lubricant, so be sure to lubricate the lock
after using
a de-icer of this type.
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Three- Way Catalytic Converter (Gasoline Engines)
Your vehicle’s three-way catalytic converter is designed to reduce the
pollutants
in your vehicle‘s exhaust. Use only unleaded fuel in your vehicle.
If you use leaded fuel, you could damage your three-way catalytic converter
and other engine components.
Oxidation Catalytic Converter (Diesel Engines)
Your vehicle’s oxidation catalytic converter is designed to reduce the
particulates
in your vehicle‘s exhaust. If your vehicle’s oxidation catalytic
converter ever needs to be replaced,
it must be replaced with an oxidation
converter intended for use
with diesel engines only.
Engine Control Module System
Gasoline Engines
This system has an oxygen sensor (OS) that helps keep your engine’s
air-fuel mixture at a proper level. Use only unleaded fuel in your vehicle. If
you use leaded fuel, you could damage your oxygen sensor
(OS) and
three-way catalytic converter.
Diesel Vehicles Below 8,500 (3 850 Kg) G VWR
This system monitors engine speed and throttle position. It adjusts exhaust
gas recirculation to limit emissions.
Malfunction Indicator (SERVICE ENGINE SOON)
Light
The Malfunction Indicator (SERVICE ENGINE SOON) Light on your
instrument panel lets you know when your emission system needs service.
The light will come on briefly when you start your engine to
let you know
that the system is working. If
it does not come on when you start your
engine, or
if it comes on and stays on while you’re driving, your system
may need service. Your vehicle should still be driveable, but you should
have your system serviced right away.
Secondary Air Injection Reaction (AIR) System
(Gasoline Engines)
You may have this system. It has a control valve that will direct air to where
it is needed. If the AIR system needs service, your Malfunction Indicator
(SERVICE ENGINE
SOON) Lamp on your instrument panel will come on.
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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:
0 Too much flexing
Too much heat
0 Tire overloading
Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation), you can get:
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.
How to Check
Use a good quality pocket-type gage to check tire pressure. Simply looking
at the tires will not tell you the pressure, especially
if you have radial tires
- which may look properly inflated even if they’re underinflated.
If your tires have valve caps, be sure to put them back on. They help prevent
leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be inspected every 6,000 to 8,000 miles (10 000 to 13 000 km)
for any signs of unusual wear. If unusual wear is present, rotate your tires as
soon as possible and check wheel alignment. Also check for damaged tires
or wheels. See “When it’s Time for New Tires” and “Wheel Replacement”
later in this section for more information.
If your vehicle has dual rear
wheels, also see
“Dual Tire Operation” later in this section.
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Finish Damage
Any stone chips, fractures or deep scratches in the finish should be repaired
right away. Bare metal will corrode quickly and may develop into
a major
repair expense.
Minor chips and scratches can be repaired with touch-up materials available
from your dealer or other service outlets. Larger areas of finish damage can
be corrected in your dealer’s body and paint shop.
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 fall upon and attack painted surfaces 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
comes 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.
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Engine Identification - Gasoline Engines
Engine
Type
VIN Code
Fuel System
Emissions
5.0L
V8
H
TBI? LD
"Light Duty Emissions with
8,500 lbs. (3 850 Kg) GVWR and below.
**Heavy Duty Emissions over 8,500 lbs. (3 850 Kg) GVWR.
?Throttle Body Injection
Engine Identification - Gasoline Engines (cont.)
Engine
Type
VIN Code
Fuel System
Emissions 7.4L
V8
N
TBI?
LD*/HD**
"Light Duty Emissions with 8,500 lbs. (3 850 Kg) GVWR and below.
""Heavy Duty Emissions over
8,500 lbs. (3 850 Kg) GVWR.
?Throttle Body Injection
Engine Identification - Diesel Engines
Engine
Type
VIN Code
Fuel System
6.5L
V8
P
Diesel
6.5L
V8 S
Turbo Diesel
6.5L
V8
F
Turbo Diesel
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CranKcase Capacity
ENGINE
4.3L 5 .OL
5.7L“
6.5L
6.5L
6.5L
7.4L>$
VIN
Z
€4
K
P
S
F
N
QUANTITY WITH
FILTER*
4.5 Quarts (4.3 Liters)
5 Quarts (4.8 Liters)
5 Quarts (4.8 Liters)
7 Quarts (6.5 Liters)
7 Quarts
(6.5 Liters)
7 Quarts (6.5 Liters)
7 Quarts (6.5 Liters)
After refill, the level
MUST be checked as outlined under “Engine Oil And
Filter Recommendations”
in Section 5.
All quantities are approximate.
“Add one additional quart for
C3500 HD Models.
+Oil filter should be changed at EVERY oil change.
Fuel Tank Capacity
TYPE
Gasoline/Diesel
with Short Bed
with Long Bed
Crew Cab
Standard
Chassis-Cab Models
Standard (Side Tank)
Optional (Rear Tank)
3500 HD Models
Standard (Side Tank)
Optional (Rear Tank)
QUANTITY
26 Gallons (98 Liters)
34 Gallons
(1 28 Liters)
34 Gallons
(1 28 Liters)
23 Gallons (87 Liters)
3
1 Gallons (1 17 Liters)
23 Gallons (87 Liters)
3 1 Gallons ( 117 Liters)
All quantities are
for a completely dry tank and are approximate.
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Service Replacement Part and Filter
Recommendations
- Gasoline Engines
Engine 4.3L
VTN Z
Oil Filter PFS2
Air Cleaner
A 178CW
Filter
PCV Valve CV789C
Spark
Plugs* .CR43TS
Fuel Filter GF48
1
Radiator Cap
RC36
5.0L
H
PF12183-
A348C
cv774c
.CR43TS
GF48
1
RC36
5.7L
K
PF1218q A348C
cv774c
.CR43TS GF38
1
RC36
+Four Wheel Drive Vehicle
- use a PFS2 oil filter
Wse AC copper-cored resistor type spark plugs
Service Replacement Part and Filter
Recommendations
- Diesel Engines
Engine 6.5L 6.5L
VIN P S
Oil Filter PF1218
PF1218
Air Cleaner A644C
A 1236C
Fuel Filter TP
1006 TP
1 006
Surge
Tank Cap RC33 RC33
7.41
N
PF1218
A348C
cv774c
.CR43TS GF48
I
RC36
6.51
F
PF1218
A 1236C
TP
I006
RC33
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Fuses and Circuit Breakers
POSITION NAME
1. STOP/HAZ
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
IS.
16.
17.
18.
19.
20.
21. 22.
T CASE
CTSY
GAGES
RR HVAC
CRUISE
AUX PWR
CRANK
PARK LPS
AIR BAG
WIPER HTR-A/C
CIG LTR
ILLUM
DRL-FOG
TURN-B/U RADIO
BRAKE RADIO
BATT
TRANS
CIRCUITS PROTECTED
Stop/TCC Switch, Buzzer, CHMSL, Hazard
Lamps, Stop Lamps
Transfer Case
Courtesy Lamps, Cargo Lamp, Glove Box
Light, Dome/RDG Lamps, Vanity Mirrors,
Pwr Mirrors
IP Cluster, DRL Relay, HDLP Switch,
Keyless Entry, Low Coolant Module
RR HVAC Controls
Cruise Control
Aux Power Outlet
Diesel Fuel Pump, DERM, ECM
Lic Lamp, Park Lamp, Tail Lamp, Roof
Marker Lamp, Tail Gate Lamps, Front Side
Markers, Fog Lamp Relay, Door Switch
Illum, Fender Lamps
DERM
Wiper Motor, Washer Pump
A/C, A/C Blower, High Blower Relay
Power Amp, Cig Lighter, Door Lock Relay,
Pwr Lumbar Seat
4WD, Indicator, LP Cluster, HVAC
Controls,
RR HVAC Controls, IP Switches,
Radio Illumination
DRL Relay, Fog Lamp Relay
Frt Turn, RR Turn, B/U Lps
Radio (Ign)
DRAC, 4WAL PCM, ABS, Cruise
Radio (Batt)
PRNDL, Auto Transmission, Speedo,
Check Gages
Tell Tale
Not Used
Not Used
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