1994 GMC SIERRA service schedule

How to Check Lubricant
What to Use
- 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.
Refer to the Maintenance Schedule to determine what kind
of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Front 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 “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
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.
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Brake Adjustment
Every time you make a brake stop, your disc brakes adjust for wear.
If your brake pedal goes down farther than normal, your rear drum brakes
may need adjustment. Adjust them by backing up and firmly applying
the
brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its many parts have to
be of top quality and work well together if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly.
For example,
if someone puts in brake linings that are wrong for your
vehicle, the balance between your front and rear brakes can change, for
the
worse. The braking performance you’ve come to expect can change in many
other ways if someone puts in the wrong replacement brake parts.
Other Maintenance Hems
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 repacked.
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 absorbers
must be
the same as the original equipment shock absorbers in both
extended length and strength.
NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers
or suspension system
could be damaged.
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Special Tire lnflation
If you have 16 inch tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 km/h) to
75 mph (120
km/h) where legal, inflate tires to 10 psi (70 kPa)
more than the recommended cold inflation pressures.
- You’ll be driving for very long at speeds of 76 mph (120 km/h) to
85 mph (135
km/h) where legal, cold inflation pressures should be
increased by
10 psi (70 kPa) and you must also reduce axle load
capacity by 10%.
Do not drive over 85 mph (135 km/h) even if
it’s legal.
Inflation pressures should never exceed 10 psi (70 kPa) above the
inflation specified for the maximum load of the tire.
If you have 19.5 inch radial tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 km/h) to
70 mph (110 km/h) where legal, inflate tires to 5 psi (35 kPa) more
than the recommended cold inflation pressures, and reduce the
axle load capacity by 4%.
- You’ll be driving for very long at speeds of 7 1 mph (1 15 km/h) to
75 mph (120
km/h) where legal, cold inflation pressures should be
increased by 5 psi (35 kPa) and you must also reduce axle \
load capacity by 12%.
Do not drive over 75 mph (120 km/h) even if
it’s legal.
Inflation pressures should never exceed 20 psi (140 kPa) above the
inflation specified for the maximum load of the tire.
Tire Inspection and Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended in the Maintenance Schedule. See “Scheduled
Maintenance Services” in the Index.
FRT
8
FRT
Use this rotation
pattern.
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Scheduled Maintenance Services
Section
This section covers the maintenance required for your General Motors
vehicle
. Your vehicle needs these services to retain it’s safety. dep\
endability.
and emission control performance
.
A Word About Maintenance .................................. 7-3
Your Vehicle and the Environment
............................. 7-3
Recording Maintenance Services
............................... 7-3
Scheduled Maintenance Services
............................... 7-4
Selecting Your Vehicle’s Maintenance Services
................. 7-4
Gasoline Engines with Light Duty Emissions
-
MaintenanceScheduleI ................................ 7-6
MaintenanceScheduleII
................................ 7-8
Maintenance Schedule I
............................... 7-10
Maintenance Schedule I1
............................. 7-12
Maintenance Schedule I
............................... 7-14
Maintenance Schedule
11 ............................... 7-16
Explanation of Scheduled Maintenance Services
............... 7-18
Owner Checks and Services
.................................. 7-22
Recommended Fluids
& Lubricants ........................... 7-25
Maintenance Record
....................................... 7-27
Service Station Checks
.... ., ................................ 7-28
Gasoline Engines with Heavy Duty Emissions
-
Diesel Engines .
Have you purchased the GM Protection Plan? The Plan supplements
the new vehicle warranties
. See your GM dealer for details .
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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
the 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
increase 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 warranty repairs.
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Tf you are skilled enough to do some work on your vehicle, you will
probably want to get the service information
GM publishes. For information
on how
to obtain various service publications for your vehicle, see “Service
Publications”
in the Index. You will find a list of publications and an order
form
in the back of the book.
Scheduled Maintenance Services
This part tells you the maintenance services that you should have 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 people
will perform the work using genuine
GM parts.
These schedules are for vehicles that:
0 carry passengers and cargo within the recommended limits. You will
find these limits on your vehicle’s Certification Label. See “Loading
Your Vehicle’’ in the Index.
are driven on regular road surfaces, and within legal driving limits, as
described in Section 4 “Your Driving and the Road.”
0 are driven off-road in the recommended manner. See “Off Road
Driving With Your Four-wheel Drive Vehicle”
in the Index.
0 use the recommended fuel. See “Fuel” in the Index.
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 vehicle.
Your engine type will tell
you which chart to use, and your driving
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 classification (Light
Duty or Heavy Duty Emissions) will
tell you which maintenance chart to
use. Find your Vehicle Identification Number (VIN), and look at the eighth
character
to see what your engine code is. Then use the following Engine
Emissions Classifications tables
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 Tndex.
If your engine has more than one emissions classification, look at your
Certification Label to see what your Gross Vehicle Weight Rating
(GVWR)
is. See “Loading Your Vehicle” in the Index.
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GASOLINE ENGINES WITH LIGHT DUTY EMISSIONS
- MAINTENANCE SCHEDULE ft
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in the Index
$ The California Air Resources Board has determined that the fail\
ure to perform this
maintenance item will not nullify the emission warranty or limi\
t recall liability prior to the
completion of vehicle useful life. General Motors, however, urge\
s that all recommended maintenance services be performed at the indicated intervals and the maintenance be
recorded.
t To determine the emissions classification of your engine, refer to “Selecting the Proper
Maintenance Chart” in this section.
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GASOLINE ENGINES WITH LIGHT DUTY EMISSIONS
- MAINTENANCE SCHEDULE 13. (continued)
If your driving conditions do NOT meet those specified in “Scheduled Maintenance Services”
in this section, use Maintenance Schedule
II (e).
-HE SERVICES SHOWN ON THIS CHART UP TO 60,000 MILES (100 000 km) ARE TO BE
)ONE AFTER 60,000 MILES AT THE SAME INTERVALS.
’0402R0902
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