1993 GMC SIERRA maintenance schedule

Hydraulic Clutch Grease Fitting
A grease fitting is on the clutch housing for lubricating the clutch fork ball
stud. See your Maintenance Schedule for when to lubricate the clutch
housing. See “Recommended Fluids and Lubricants” in the Index for the
proper lubricant to use.
Be sure not to over-fill because you could damage your clutch.
Four- Wheel Drive
Most lubricant checks in this section also apply to four-wheel-drive vehicles.
However, they have two additional systems that need lubrication.
Transfer Case
When to Check Lubricant:
Refer to the Maintenance Schedule to determine how often to check the
lubricant. See “Periodic Maintenance Inspections” in the Index.
How to Check and Add Lubricant:
I
PO230
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant. Add enough lubricant to raise the level to the bottom of the
filler plug hole.
What to Use:
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
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Senrice d& Appearance Cam
Front Axle
When to Check and Change Lubricant:
Refer to the Maintenance Sched,ule to determine
lubricant and when to change it. See “Scheduled
the Index.
How to Check Lubricant:
how often to check the Maintenance Services” in
PO231
If the. level is below the bottom of the filler plug hole, you’ll need to add
some lubricant. If the differential is at operating temperature (warm), add
enough lubricant to raise the level to the bottom
of the filler plug hole.
If the differential is cold, add, enough lubricant to raise the level to 1/2 inch
(12 mm) below the filler plug hole.
What to Use:
Refer to the Maintenance Schedule to determine what .kind of lubricant to
use. See “Recommended Fluids and Lubricants’’ in the Index.
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Rear Axle
When to Check and Change Lubricant:
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change it. See “Recommended Fluids and Lubricants”
in the Index.
How to Check iubricant:
L
PO592
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant. Add enough lubricant
to raise the level to the bottom of the
filler plug hole.
What to Use:
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
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When the engine compartment is hot, the level should be at the FULL
When the engine compartment is cool, the level should be at the FULL
mark.
COLD mark.
F
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K2694
What to Add:
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants’’ in the Index.
r
When adding power steering fluid or making a complete fluid change, I
always use the proper fluid. Failure to use the proper fluid can cause
leaks and damage hoses and seals.
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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
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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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