1993 GMC SIERRA Index

Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
K2470
There are only two reasons why the brake fluid level in your \
master cylinder
might go down. The first is that the brake fluid goes down to an acceptable
level during normal brake lining wear. When new linings are put in, the fluid
level goes back up. The other reason is that fluid is leaking out of the brake
system.
If it is, you should have your brake system fixed, since a leak means
that sooner or later your brakes won’t work well, or won’\
t work at all.
So, it
isn’t a good idea to “top
off” your brake fluid. Adding brake fluid won’t correct
a leak.
If you add fluid when your linings are worn, then you’ll have too
much fluid when you get new brake linings. You should add (or remove), \
brake fluid, as necessary only when work is done on the brake\
hydraulic
system.
CAUTION I
If you have too much brake fluid, it can spill on the engine. The fluid
and your vehicle could be damaged. Add
. ake fhid nnlv en wn
is done on the brake hydraulic system.
- will burn if the engine is hot enough. You or others could he burned
Refer
to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance” in the index.
To Check Brake Fluid:
You can check the brake fluid without taking off the cap. Just look at the
windows on the brake fluid reservoir. The fluid levels should be above the
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Other Maintenance Items
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings. See
“Recommended Fluids and Lubricants’’ in the Index for the proper lubricant to
use.
Front Wheel Bearings
Your vehicle has front wheel bearings that must be cleaned and repa\
cked.
Your maintenance schedule will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control the travel
of the suspension system.
When the shock absorbers are serviced, any replacement shock absorber\
s
must be the same as the original equipment shock absorbers in both
extended length and strength.
1 NOTICE
If you use shock absomers that are nor me same as the original shock
I absorbers, the shock absorbers or suspension system could be da\
maged.
Wheel Nut Torque
For vehicles with dual wheels, when the vehicle, wheel or fast\
eners are new,
have the torque set at the first
100, 1,000 and 6,000 miles (160, 1600 and
9600 km). Use the torque specified in the appropriate Specification \
Chart later
in this section.
Single Belt Accessory Drive
If your new vehicle uses a serpentine belt, it is lighter, and more durable
than systems with several belts.
The belt runs over or around the pulleys
on the engine. A tensioner is used
to keep the belt tight at all times. The tensioner also makes replacing the
belt easier.
If you need to replace the belt, be sure to get the correct
replacement belt. Your dealership
or parts supplier can help you with this.
The Accessory Drive Belt Routing label on your vehicle will sh\
ow you how to
route the belt your vehicle uses.
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
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 conditi\
oning 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\
possible.
The air conditioning will not work when the temperature is bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface 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.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and \
Lubricants” in
the Index for the proper lubricant to use.
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Accelerator cables and cruise control cables should not be lubr\
icated. Any
cables that are worn or are hard to pull should be replaced. \
Remove external deposits from injector pump face cam on 6.2L d\
iesel
engines, when the engine is cold.
Hood Latches and Hood Hinge
Your maintenance schedule will tell you how often to lubricate the \
hood latch
and hood hinge assembly. See “Recommended Fluids and Lubrican\
ts” in the
Index for the proper lubricant to use.
Propeller Shaft Slip Splines
See your maintenance. schedule to find out how often the slip \
splines must
be lubricated. See “Recommended Fluids and Lubricants” in \
the Index for the
proper lubricant to use.
Constant Velocity Joints
See your maintenance schedule to find out how often the consta\
nt velocity
joints must be lubricated. See “Recommended Fluids and .Lubri\
cants” in the
Index for the proper lubricant to use.
80dy
Normal use of your vehicle will cause metal to metal wear at some points on
the cab and body
if they are not lubricated.
For exposed surfaces, such as door checks, door lock bolts, lo\
ck striker
plates, dovetail bumper wedges, etc., a thin film of engine oil should be
applied.
The seat adjusters and seat track should be lubricated with chassis grease.
Door weather strips and rubber hood bumpers should be lightly coated with a
rubber lubricant.
Never use too much of any lubricant and be sure to wipe up any extra
lubricant when you are finished.
Your maintenance schedule
will tell you how often to lubricate these Ilems.
See “Recommended Fluids and Lubricants” in the Index for \
the proper
lubricant to use.
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.
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Service & Appearance Care
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.
Tailgate Handle
The tailgate handle pivot points on your vehicle should be lub\
ricated to keep
it working smoothly.
Your maintenance schedule will tell you how often to lubricate the handle.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Electrical System
Battery
Every new GM vehicle has a Delco Freedom@ battery. You never have to
add water to one of these. When it’s time for a new battery, we recomme\
nd
a Delco Freedom@ battery. Get one that has the catalog number \
shown on
the original battery’s label.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or more, take off the
black, negative
(-) cable from the battery. This will help keep your battery
from running down.
I - Batteries have acid that can burn you and gas that can explod\
e. You I
1 can be badly hurt if you aren’t careful. See “Jump Starting” in the
Index for tips on working around a battery without getting hur\
t.
Contact your dealer to learn how to prepare your vehicle for longer periods.
Bulb Replacement
Before you replace any bulbs, be sure that all the lights are off and the
engine isn’t running.
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Service & Appearance Care
4. Push in gently on the bulb, turn it counterclockwise and remove it from
the socket.
5. Put in a new bulb and, pushing in gently, turn it clockwise until it is
tight.
6. Put the socket back in the light assembly and replace the lens and lens
seal.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from short circuits by a
combination of fuses, circuit breakers, and fusible thermal links in the wiring
itself. This greatly reduces the chance of fires caused by electrical problems.
See “Fuses and Circuit Breakers’’ in the Index for more information.
Headlights
The headlight wiring is protected by a circuit breaker in the light switch. An
electrical overload will cause the lights to go on and
off, or in some cases to
remain
off. If this happens, have your headlight wiring checked right away.
Windshield Wipers
The windshield wiper motor is protected by a circuit breaker a\
nd a fuse. If
the motor overheats due
to heavy snow, etc., the wiper will stop until the
motor cools.
If the overload is caused by some electrical problem and not
snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers in the fuse panel protect the power windows and other power
accessories. When the current load is too heavy, the circuit breaker opens
and closes, protecting the circuit until the problem is fixed or goes away.
Trailer Wiring Harness
The optional seven-wire trailer wiring harness is protected by an in-line fuse
in the battery feed wire. This fuse is near the junction block. See “Trailer
Wiring Harness” in the Index for more information.
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Fuse Block
K2644
The fuse block is in the instrument panel on the driver’s side.
You can remove fuses with a fuse extractor,
if you have one. To remove
fuses
if you don’t have one, hold the end of the fuse between your thumb
and index finger and pull straight out.
Be sure
to use the correct fuse. If you ever have a problem on the road and
don’t have a spare fuse, you can “borrow’’ one of the correct value. Just pick
some feature
of your vehicle that you can get along without-like the radio or
cigarette lighter-and use its fuse,
if it is of the value you need. Replace it
as soon as you can. See “Fuses and Circuit Breakers” in the Index for more
information.
Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle
if you notice:
Engine misfiring
Loss of performance
Other unusual operating conditions
Have your engine and exhaust system serviced regularly.
Three- Way Cataiytic Converter
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
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Service & Appearance Care
Trailer Recommendations
You must subtract your hitch loads from the CWR for your vehicle. Weigh
your vehicle with your trailer attached,
so that you won’t go over the GVWR
or the GAWR.
You’ll get the best performance
if you spread out the weight of your load the
right way, and
if you choose the correct hitch and trailer brakes.
For more information, see “Trailer Towing” in the Index.
If you want more information on curb weights, cargo weights, cargo wei\
ght
rating and the correct center of gravity zone for your vehicle, your dealer can
help you. Just ask for a copy of “Consumer Information, Truck-Cam\
per
Loading.”
Pickup Conversion lo. Chassis Cab
General Motors is aware that some vehicle owners may consider having the
pickup box removed and a commercial
or recreational body installed. Before
you do
so, first contact the GM Zone Office for your area for information on
such conversions. (See the “Warranty and Owner Assistance”\
booklet for
Zone Office.) Owners should be aware that, as manufactured, th\
ere are
differences between a chassis cab and a pickup with the box r\
emoved which may affect vehicle safety. The components necessary to adapt the pickup to
permit its safe use with a specialized body should be installed by a bod\
y
builder in accordance with the information available from the Z\
one Office.
Tires
We don’t make tires. Your new vehicle comes with high quali\
ty tires made by
a leading tire manufacturer. These tires are warranted by the \
tire
manufacturers and their warranties are delivered with every new \
vehicle.
If
your spare tire is a different brand than your road tires, you will have a tire
warranty folder from each of these manufacturers.
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