1993 GMC SIERRA fuel

you use leaded fuel, you could damage your three-way catalytic converter,
and other engine components.
Computer Command Control System (All TBI equipped
vehicles and diesel engine vehicles below
8,500 lbs. GVWR)
Gasoline Engines
This system has an oxygen (OS) sensor that helps keep your engine’s air-fuel
mixture at a proper level. Use only unleaded fuel in your veh\
icle.
If you use
leaded fuel, you could damage your oxygen
(OS) sensor and three-way
catalytic converter.
Diesel Vehicles Below 8,500 LBS. GVWR
This system monitors engine speed and throttle position. It adj\
usts exhaust gas recirculation to limit emissions.
The Malfunction Indicator Lamp
(SERVICE ENGINE SOON) on your
instrument panel lets you know when your emission control syste\
m needs
service. The light will come on briefly when you start your e\
ngine 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 (AIR) System
You may have this system. It lets you know if your engine control module,
wiring harness or solenoid need service.
If the Malfunction Indicator Lamp
(Service Engine Soon) comes on, you need service.
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Loading Your Vehicle
The CertificationKire label is found on the rear edge of the driver’s door or in
the incomplete vehicle document in the cab. The label shows th\
e size of your
original tires and the inflation pressures needed
to obtain the gross weight
capacity of your vehicle. This is called the GVWR (Gross Vehicle Weight
Rating). The
GWVR includes the weight of the vehicle, all occupants, fuel and
cargo.
The CertificationKire label also tells you the maximum weights for the front
and rear axles, called Gross Axle Weight Rating (GAWR). To find out the
actual loads on .your front and rear axles, you need to go to a weigh station
and weigh your vehicle. Your dealer can help you with this. .Be sure to
spread out your load equally on both sides of the centerline+
.. , - :I. -I lrT1 I I -
Never exceed the GVWR for your vehicle, or the Gross, Axle Weight Rating-
(GAWR) for either the front or rear axle.
And,
if you do have a heavy load, you should spread it out.
. -1 r,
In the case of a sudden stop or collision, things carried in the bed of 7
injuring you and others. If you put things in the bed of your truck,
you should make sure they are properly secured.
r! your truck could shift forward and come into the passenger are\
a,
-
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Service & Appearance Care
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 materia\
ls 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 wi\
th 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 washing system can do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a chemical fallout.
Airborne pollutants fall upon and attack painted surfaces on yo\
ur vehicle. This
damage
can take two forms: blotchy, ringiet-shaped discolorations, and small\

irregular dark spots etched into the paint surface.
Although no defect in the paint job causes this, General Motors 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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Specification Charts
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.
Engine Identification
Liter Produced Fuel VIN
Displacement Type
U.S. TBI N
V8 7.4 H.D.
us. Diesel F V8 6.5
H.D. U.S. Diesel J V8 6.2
L. D. us. Diesel C V8 6.2
US., Can.
TBI K V8
5.7
L. D. US., Can.
TBI H
V8 5.0
U.S. TBI 2 V6
4.3
Emissions
BY
System
Engine Code
*
*
*
*Light Duty Emissions with 8500 GVWR and below or:
Heavy Duty Emissions with 8501 GVWR and above.
TO035
Wheel Nut Torque
MODEL I DESCRIPTION I TORQUE I
C 1500 5 bolts (14mm) 120 ft. Ibs. (160 Nmm)
K 1500 & C-K 2500 6 bolts f14mm) 120 ft. Ibs. (1 60 N.m)
C-K
2500 (w/C6P) 8 bolts (14mm) 120 ft. Ibs. (160 Nmm)
C-K 3500 Single Rear Wheels 8 bolts (14mm) 120
ft. Ibs.
(1 60 N-m)
C3500 Dual Rear Wheels
8 bolts (14mm) 140 ft. Ibs. (190
N-m)
C3500 HD -Front
5 bolts (5/8 in.) 175 ft. Ibs. (240 Nsm)
TO040
--Rear
10 bolts (5/8 in.)
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Air Conditioning Refrigerant Capacity
TYPE* QUANTITY
Refrigerant R-12 2.5 Ibs. (1.1 34 kg)
*Not all air conditioning refrigerants are the same. If the air conditioning
system in your vehicle needs refrigerant, be sure the proper r\
efrigerant is
used.
If you’re not sure, ask your GM dealer.
TO223
Fuel Tank Capacity
TYPE
Gasoline, Diesel with Short Bed
with Long Bed
Four Door Model
Standard
Chassis-Cab Models Standard (Side Tank)
Optional (Rear Tank)
Standard (Side Tank)
Optional (Rear Tank)
3500 HD Models
QUANTITY
-
.-
-
All quantities are for a completely dry tank and are approximate.
TO1
8C
26 Gallons (98 Liters)
34 Gallons (128 Liters)
34 Gallons
(1 28 Liters)
22 Gallons (83 Liters)
30 Gallons
(1 13 Liters)
21 Gallons (80 Liters)
32 Gallons (121 Liters)
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I I Power Rating I 1
Lamp or Bulb
Malfunction Indicator (“Service Engine
Quantity
at 12.8V, Watts Trade No.
Soon”)
“Diesel only
**Crew Cab Only tCanadian Vehicles only t0390
1 .7
74
Service Fuel Filter Lamp*
1 .7
74
Low Coolant Lamp*
1 .7 74 Glow Plugs Lamp*
1 .7
74
Upshift Indicator
1 .7
74
Service Replacement Part and Filter Recommendations
Engine
(VIN)
4.3 (Z)
5.0 (H)
5.7 (K)
6.2 (C)
6.2
(J)*
6.5 (F)*
7.4
(N)
-
Oil
Filter
PF51
PF35t
PF35t
PF35
PF35
PF35
PF35
-
Air
Cleaner
A1 78CW A348C
A348C
A644C A644C
A917C
A348C
PCV
Valve
CV789C
cv774c
cv774c
-
-
-
cv774c I I
tFour Wheel Drive Vehicles use a PF51
*Heavy
Duty Emission Engine
1,
Spark** Plugs
CR43TS
.CR43TS
.CR43TS
-
-
.CR43TS
oil filter
’*Use AC copper-cored resistor type spark plugs.
Fuel
Filter
GF481
GF481
GF481
TP 1
006
TP 1 006
TP1006
GF481
-I
RC36
RC36
RC32
RC32
RC32
RC36
t0039
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Scheduled Maintenance Services
Scheduled Maintenance Services
This part tells you the maintenance services that you should h\
ave done and
the times you should schedule them. Your GM dealer knows your vehicle best
and wants you
to be happy with it. If you go to your dealer for your service
needs, you’ll know that GM-trained and supported service peop\
le will perform
the work using genuine GM parts.
These schedules are for vehicles that:
carry passengers and cargo within the recommended limits. You will find
these limits on your vehicle’s Certification Label. See “L\
oading Your
Vehicle” in the Index.
are driven on regular road surfaces, and within legal driving \
limits.
are driven off-road in the recommended manner. See the Index U\
nder
use the recommended fuel. See “Fuel” in the Index.
“Off Road Driving With Your Four Wheel Drive Vehicle.”
selecting The Proper Maintenance Services
To find the proper maintenance schedule for your vehicle, you must\
know two
things. What engine your vehicle has, and how you use your ve\
hicle. Your
engine type will tell you which chart to use, and your drivin\
g conditions will
tell you which schedule to use. The charts are found later in\
this section.
Selecting the Proper Maintenance Chart
Your engine type (Gasoline or Diesel) and its emissions classificat\
ion (Light
Duty 3r Heavy Duty Emissions) will tell you which maintenance \
chart
to use.
Find your Vehicle Identification Number (VIN), and look at th\
e eighth character
to see what your engine code is. Then use the following Engine E\
missions
Classifications table
to find your emissions classification.
Your VIN is on the plate on the top left corner of your instrument panel,
the Certification Label and on the Service Parts Identification \
Label. See “Vehicle Identification Number” in the Index.
If your engine has more than one emissions classification, look at\
your
Certification Label to see what your Gross Vehicle Weight Ratin\
g
(GVWR)
is. See “Loading Your Vehicle” in the Index.
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6. AIR CLEANER FILTER REPLACEMENT* -Replace at every 30,000
miles (50 000 km) or more often under dusty conditions. Ask your dealer
for the proper replacement intervals for your driving conditions\
.
7. FRONT WHEEL BEARING REPACK (2 WHEEL DRIVE ONLY) -Clean
and repack the front wheel bearings at each brake relining, or\
at the specified interval, whichever comes first.
8.
TRANSMISSION SERVICE
Automatic Transmission
-Change the transmission fluid and filter every
15,000 miles (25 000 km) for vehicles under 8,600 GVWR or every
12,000 miles (20 000 km) for vehicles over 8,600 GVWR if the vehicle
is mainly driven under one or more of these conditions:
In heavy city traffic.
Where the outside temperature regularly reaches 90°F (32°C\
) or
higher.
In hilly or mountainous terrain.
Frequent trailer pulling.
Uses such as taxi, police, delivery or other commercial service\
.
If the vehicle is not used mainly under any of these conditions, change
the fluid and filter every 30,000 miles
(50 000 km) for vehicles under
8600 GVWR or every
24,000 miles (40 000 km) for vehicles over 8600
GVWR. See “Automatic Transmission Fluid” in the Index for more
information.
Manual Transmission -Transmission fluid does not require periodic
changing.
Regulator Valve System for any worn, plugged or collapsed hoses. Have
the system checked as described in the Service Manual.
9.
CDRV SYSTEM INSPECTION* -Check
the Crankcase Depression
10. FUEL FILTER REPLACEMENT* -Replace the fuel filter at the specified
interval
or sooner if clogged.
11. SPARK PLUGS REPLACEMENT* -Replace spark plugs with the type
listed in Section
6. See “Specification Charts” in the Index.
12.
SPARK PLUG WIRE INSPECTION* -Clean wires and inspect for burns,
cracks or other damage. Check the wire boot fit at the distributor and at
the spark plugs. Replace wires as needed.
*An Emission Control Service
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