1999 GMC SUBURBAN service

6-40
When It's Time for New Tires
One way to tell when it's
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of
tread remaining.
You need a new tire if any of the following statements
are true:

You can see the indicators at three or more places
around the tire.

You can see cord or fabric showing through the
tire's rubber.

The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge or split.

The tire has a puncture, cut or other damage that
can't be repaired well because of the size or location
of the damage.
Buying New Tires
To find out what kind and size of tires you need,
look at the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire's sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service
on your vehicle. If your tires have an all
-season tread
design, the TPC number will be followed by an ªMSº
(for mud and snow).
If you ever replace your tires with those not having
a TPC Spec number, make sure they are the same
size, load range, speed rating and construction type
(bias, bias
-belted or radial) as your original tires.

6-42
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and a half
(1 1/2) times as well on the government course as a tire
graded 100. The relative performance of tires depends
upon the actual conditions of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction
-- AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire's ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight
-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.Temperature
-- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire's resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must meet
under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and
not overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.

6-51
Use chrome polish only on chrome-plated wheels,
but avoid any painted surface of the wheel, and buff off
immediately after application.
Don't take your vehicle through an automatic car wash
that has silicon carbide tire cleaning brushes. These
brushes can also damage the surface of these wheels.
Cleaning Tires
To clean your tires, use a stiff brush with a tire cleaner.
NOTICE:
When applying a tire dressing always take care
to wipe off any overspray or splash from all
painted surfaces on the body or wheels of the
vehicle. Petroleum
-based products may damage
the paint finish and tires.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti
-corrosion material to the parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide
the corrosion protection while maintaining the warranty.
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
materials available from your dealer or other service
outlets. Larger areas of finish damage can be corrected
in your dealer's body and paint shop.

6-54
Vehicle Identification Number (VIN)
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 can 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 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Parts Identification Label
You'll find this label located in the glove box. It's very
helpful if you ever need to order parts. On this label is:

your VIN,

the model designation,

paint information and

a list of all production options and
special equipment.
Be sure that this label is not removed from the vehicle.

6-67
Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are based on the latest information available at the time of printing,
and are subject to change. If a part listed in this manual is not the same as the part used in your vehicle when it was
built, or if you have any questions, please contact your GM dealer.
These specifications are for information only. If you have any questions, see the service manual for the chassis or
refer to the body manufacturer's publications.
VIN Code V T U
Oil Filter* PF59 PF59 PF59
Engine Air Cleaner/Filter*
A1519C
A1519C
A1518C
Passenger Compartment Air Filter Kit** 52485513 52485513 52485513
PCV Valve* CV948C CV948C CV948C
Spark Plugs*


41
-952 41-952 41-952
Fuel Filter* GF626 GF626 GF626
Wiper Blades (Front) ** 15706394 15706394 15706394
Wiper Blade Type (Front) ITTA ITTA ITTA
Wiper Blade Length (Front) 22 inches (56.0 cm) 22 inches (56.0 cm) 22 inches (56.0 cm)
Wiper Blades (Rear) ** 22154396 22154396 22154396
Wiper Blade Type (Rear) ITTA ITTA ITTA
Wiper Blade Length (Rear) 18 inches (45.0 cm) 18 inches (45.0 cm) 18 inches (45.0 cm)
*AC part number
**GM part number

A1518C high
-capacity air cleaner filter may be substituted.


Spark Plug Gap is 0.060 inches

7-
7-1
Section 7 Maintenance Schedule
This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
7
-2 Introduction
7
-4 Part A: Scheduled Maintenance Services
7
-5 Scheduled Maintenance7
-16 Part B: Owner Checks and Services
7
-21 Part C: Periodic Maintenance Inspections
7
-23 Part D: Recommended Fluids and Lubricants
7
-26 Part E: Maintenance Record

7-3 How This Section is Organized
This maintenance schedule is divided into five parts:
ªPart A: Scheduled Maintenance Servicesº shows
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you should
let your dealer's service department or another qualified
service center do these jobs.
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 qualified
technician do the work.
If you want to get the service information, see ªService
and Owner Publicationsº in the Index.ªPart B: Owner Checks and Servicesº tells you
what should be checked and when. It also explains
what you can easily do to help keep your vehicle in
good condition.
ªPart C: Periodic Maintenance Inspectionsº
explains important inspections that your dealer's
service department or another qualified service center
should perform.
ªPart D: Recommended Fluids and Lubricantsº lists
some recommended products necessary to help keep
your vehicle properly maintained. These products, or
their equivalents, should be used whether you do the
work yourself or have it done.
ªPart E: Maintenance Recordº is a place for you
to record and keep track of the maintenance performed
on your vehicle. Keep your maintenance receipts.
They may be needed to qualify your vehicle for
warranty repairs.

7-4
Part A: Scheduled
Maintenance Services
Using Your Maintenance Schedule
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
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read the
following and note how you drive. If you have any
questions on how to keep your vehicle in good
condition, see your dealer.This part tells you the maintenance services you should
have done and when you should schedule them. 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.
The proper fluids and lubricants to use are listed in
Part D. 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 vehicle.
This schedule is for vehicles that:

carry passengers and cargo within recommended
limits. You will find these limits on your vehicle's
Certification/Tire label. See ªLoading Your Vehicleº
in the Index.

are driven on reasonable road surfaces within legal
driving limits.

are driven off
-road in the recommended manner. See
ªOff
-Road Driving With Your Four-Wheel-Drive
Vehicleº in the Index.

use the recommended fuel. See ªFuelº in the Index.