1993 GMC SIERRA air condition

Wheel Replacement
Re'place any' wheel that is bent, cracked or badly rusted. If wheel nuts keep
coming loose, the wheel, wheel bolts, and wheel nuts should be\
replaced.
If
the wheel leaks air out,, replace it (except some aluminum wheels, which can
sometimes be repaired). See your GM dealer
if any of these conditions
exists. Your dealer will know what kind of wheel you need.
Each new wheel should' have the same load carrying capacity, d\
iameter,
width, offset, and be mounted the same way as the one it' replaces.
If you need to replace any of'your wheels, wheel bolts, or wheel nuts,
replace them only with
new GM original equipm-ent parts. This way, you will
be sure to have the right ,wheel, wheel bolts, .and wheel nuts for your vehicle.
1 CAUTION
Using the wrong replacement wheels, wheel bolts or wheel nuts \
on
your vehicle can be dangerous.
It could affect the braking and
handling of your vehicle, make your tires lose air and make you lose
control. You could have an collision in which you or others could be
injured. Always use the correct wheel, wheel bolts, and wheel \
nuts
for redacement.
I
NnTICF
I
Used Replacement Wheels
* Putting a used wheel on your vehicle is dangerous. You can't know
1 how it's been used or how many miles it's been driven. It could fail
suddenly and cause an accident.
If you have to replace a wheel, use
I a new GM original equipment wheel.
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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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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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A Word About Maintenance
We at General Motors want to help you keep your vehicle in good working
condition. But we don’t know exactly how you’ll drive it. You may drive very
short distances only a few times a week. Or you may drive long distances all
the time in very hot, dusty weather. You may use your vehicle in making
deliveries. Or you may drive it
to work, to do errands, or in many other ways.
Because of all the different ways people use their GM vehicles, maintenance
needs vary. You may even need more frequent checks and replacements than
you will find in the schedules in this section.
So please read this section and
note how you drive.
If you have any questions on how to keep your vehicle
in good condition, see your GM dealer, the place many GM owners choose
to have their maintenance work done. Your dealer can be relied upon to use
proper parts and practices.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps keep your vehicle in good working
condition, but also helps the environment. All recommended maintenance
procedures are important. Improper vehicle maintenance or the removal of
important components can significantly affect the quality of the air we breathe.
Improper fluid levels or even the wrong tire inflation can inc\
rease the level of
emissions from your vehicle. To help protect our environment, and to help
keep your vehicle in
good condition, please maintain your vehicle properly.
Recording Maintenance Services
The Maintenance Record near the end of this section provides a place for
you
to record the maintenance performed on your vehicle. Whenever any
maintenance is performed, be sure
to write it down in the Maintenance
Record. This will help you determine when your next maintenance should be
done, In addition, it is a good idea to keep your maintenance receipts. They
may be needed to qualify your vehicle for warranty repairs.
CAUTION
+ CAUTION: Performing maintenance work on a vehicle can be
dangerous. In trying
to do some jobs, you can be seriously injured.
Do your own maintenance work only if you have the required
know-how and the proper tools and equipment for the job.
If you
have any doubt. have
a aualified technician do the work.
If you are skilled enough to do some work on your vehicle, you will probably
want to get the service information GM publishes. You will
find a list of
publications and how to get them in the back of Section
8, “Customer
Assistance Information.” See “Service Publications’’ in the Index.
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6.2L AND 6.5L DIESEL ENGINES-
-0OTNOTES:
rt Change filter every 15,000 miles (24 000 km), except when operating in dusty
conditions. Dusty conditions may require more frequent filter re\
placement. Extreme
dust and dirt operating conditions (off-road), may require the air filter
to be
checked as often as every 300 miles (483 km) and replaced as necessary.
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in this section.
1 Applicable only to trucks sold in the United States.
A Also, a Noise Control Service (applicable to vehicles with engine VIN Code J).
t This maintenance schedule applies to all diesel engines available. TO330
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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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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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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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