1993 GMC SIERRA Specifications

Service & Appearance Care
1 If you try to do your own service work without knowing enough ab\
out it, I
1 your vehicle could be damaged.
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains the \
maintenance your new vehicle needs, and when
it -should be done. It also,
has a form that you can use to record the maintenance work done \
on your
vehicle. Be sure to read this ,information.
-I .. >. ’ , .
Fuel (Gasoline Engines)
If your vehicle has a diesel engine, see “Diesel Fuel Requi\
rements and Fuel
System’’ in this Section: For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at 87 octane or’higher.
It should meet
specifications ASTM D4814 in the
U.S. and CGSB 3.592 in Canada. These
fuels should have the proper additives,
so you should not have to add
anything to the fuel.
In the
U.S. and Canada, it’s easy to be sure you get the right kind of
gasoline (unleaded). You’ll see
UNLEADED right on the pump. And only
unleaded nozzles
will fit into your vehicle’s filler neck.
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.
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Cleaning Your Diesel Engine
you spray or pour water or any other liquid on your engine when it is
arm or hot,
or when it is running, you could cause serious damagl o it.
you ever clean the engine, clean it only when it is cold.
Noise Control System
The following information relates to compliance with Federal noi\
se emission
standards for vehicles with a Gross Vehicle Weight Rating (GVW\
R) of more
than 10,000 pounds
(4 536 kilograms). See your maintenance schedule for
information on maintaining the noise control system to minimize degradation
of
the noise emission control system during the life of your vehicle. The noise
control system warranty is given in your Warranty booklet.
These standards apply only to vehicles sold in the United States.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing thereof:
1. The removal or rendering inoperative by any person, other t\
han for purposes of maintenance, repair or replacement, of any device
or
element of design incorporated into any new vehicle for the purpose of
noise control, prior to its sale or delivery to the ultimate purchaser or
while it is in use;
or
2. The use of the vehicle after such device or element of design has been
removed or rendered inoperative by any person.
Among those acts presumed to constitute tampering are the acts listed below.
Insulation:
Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor, if so equipped, inoperative
so as to allow engine speed to exceed manufacturer specifications.
Fan and Drive:
Removal of fan clutch, if so equipped, or rendering clutch inoperative.
Removal of fan shroud, if so equipped.
Air Intake:
Removal of air cleaner silencer.
Reversing air cleaner cover.
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When to Add Oil: If the oil is at or below the ADD mark, then you’ll need
to add some oil. But you must use the right kind. This part explains what
kind
of oil to use. For crankcase capacity, see “Capacities and Specifications”
in the Index.
Don’t add too much
oil. If your engine has so much oil that the oil level
gets above the upper mark that shows the proper operating range, your
engine
could be damaged.
I
.I a.. ;
K2390
Just fill it enough to put the level somewhere in the proper operating range.
Push the dipstick all the way back in when you’re through.
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Service & Appearance Care
Vehicle identification Number (VIN)
KO641
This is the legal identifier for your vehicle. It appears on a plate in the front
corner of the instrument panel, on the driver’s side. You c\
an see it if you
look through the windshield from outside your vehicle. The VIN also \
appears
on the Vehicle Certification and Service Parts labels and the \
certificates of
title and registration.
Engine Identification
The eighth character in your VIN is the engine code for your \
GM engine.
This code will help you identify your engine, specifications, a\
nd replacement parts in this section.
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Scheduled Maintenance Services
Explanation Of Scheduled Maintenance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. Make sure
whoever services your vehicle uses these. All parts should be \
replaced and
all necessary repairs done before you or anyone else drives the ve\
hicle.
1.
ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SG OR
SGKE QUALITY, ENERGY CONSERVING II OILS OF THE PROPER
VISCOSITY. To determine the preferred viscosity oil for your vehicle’s
engine (e.g. SAE 5W-30 or 10W-30), see “Engine Oil” in the Index.
2. CHASSIS LUBRICATION -Lubricate the front suspension, king pin
bushings, steering linkage, transmission, and transfer case shift\
linkage,
parking brake cable guides, propshaft splines (2 wheel drive), brake
pedal springs, and clutch pedal springs at the intervals specified.
If you have a 3500 HD, lubricate the king pins and king pin bushings
every 1,500 miles
(2500 km) for Maintenance Schedule 1, or every 3,000
(5000 km) for Maintenance Schedule 2.
Ball joints and king pin bushings should not be lubricated unless their
temperature is
10°F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or they could be damaged.
Also, be sure to check
all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION -Lubricate the clutch fork
ball stud through the fitting on the clutch housing. Lubricant must be
added “sparingly” to the fitting, as only.
0066 Ib. (.003 kg) is required to
lubricate the ball stud surface.
Do not add lubricant more often than the
intervals in the Maintenance Charts.
Too much lubricant will damage
the clutch assembly.
4. ENGINE IDLE SPEED ADJUSTMENT (DIESEL ENGINES)* -Adjust to
the specifications shown on the underhood label. You must use
calibrated test equipment.
5. COOLING SYSTEM SERVICE* -Drain, flush and refill system with new
coolant. See “Engine Coolant’’ in the Index for the proper coolant and
mixture to use in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension \
clamps).
Remove debris and clean the outside
of the radiator and air conditioning
condenser. Wash the radiator neck.
To ensure proper operation, pressure
test the radiator and cap.
* An Emission Control Service
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Scheduled Maintenance Services
13. EGR SYSTEM INSPECTION* -Conduct EGR SYSTEM CHECK as
described in the Service Manual.
14. ELECTRONIC VACUUM REGULATOR VALVE (EVRV) INSPECTION*
-Inspect filter for excessive contamination or plugging. If required, clean
element with a solution of biodegradable soap and water, let
dry and
reinstall element.
15. ENGINE TIMING CHECK AND DISTRIBUTOR CHECK (SOME
MODELS)”
-Adjust timing to underhood label specifications. Inspect the
inside and outside of the distributor cap and rotor for cracks, carbon
tracking and corrosion. Clean or replace as needed.
cap and lines for damage or leaks. Remove fuel cap, inspect g\
asket for
an even filler neck imprint, and any damage. Replace parts as \
needed.
16. FUEL TANK, CAP AND LINES INSPECTION* -Inspect the fuel tank,
17. THERMOSTATICALLY CONTROLLED AIR CLEANER INSPECTION*
A-(If so equipped.) Inspect all hoses and ducts for proper hookup.
Make sure valve works properly.
Look for cracks, fraying, wear, and proper tension. Adjust or replace as
needed.
19. EVAPORATIVE CONTROL SYSTEM (ECS) INSPECTION* -Check all
fuel and vapor lines and hoses for proper hookup, routing, and\
condition.
Check that the purge valve works properly,
if equipped. Replace as
needed.
18. ENGINE ACCESSORY DRIVE BELT(S) INSPECTION* --Inspect belts.
20. SHIELDS AND UNDERHOOD INSULATION INSPECTION Am-Inspect
shields and underhood insulation for damage or looseness. Adjust\
or
replace as required.
21. AIR INTAKE SYSTEM INSPECTlONAWCheck the air intake system
installation to see that gaskets are seated properly and all hose
connections, fasteners, and other components are tight. Also check to be
sure that the air cleaner housing is properly seated, that the\
cover fits
tightly, and the wing nuts are tight. Tighten connections and \
fasteners or
replace damaged parts as required.
22. THERMOSTATICALLY CONTROLLED ENGINE COOLING FAN INSPECTI0NA.-(If
so equipped.) With the engine off and below
normal operating temperature, check to see that the fan can be rotated
by hand on fluid coupling or viscous drives. Replace as necessary.
*An Emission Control Service
AAlso a Noise Emission Control Service
.Applicable only to vehicles
sold in the United States
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