1993 BUICK RIVIERA service

When to Change Engine Oil: See if any one of these is
true for you:
Most trips are less than 4 miles (6 km).
a It’s below freezing outside and most trips are less
than
10 miles (16 km).
0 The engine is at low speed most of the time (as in
door-to-door delivery, or in stop-and-go traffic).
Most trips are through dusty places.
If any one of these is true for your vehicle, then you
need to change your oil and filter every
3,000 miles
(5 000 km) or 3 months -- whichever comes first.
If none of them is true, change the oil every 7,500 miles
(12
500 km) or 12 months -- whichever comes first.
Change the filter at the first oil change and at every
other oil change after that.
Engine Block Heater: An engine block heater can be a
big help if you have to park outside in very cold
weather, -20
OF (-29 C) or colder. If your vehicle has
this option, see ?Engine Block Heater”
in the Index.
What to Do with Used Oil:
1
Used oil can be a real threat to the environment. If you
change your own oil, be
sure to drain all free-flowing oil
from the filter before disposal. Don’t ever dispose of oil
by pouring it on the ground, into sewers, or into streams
or bodies
of water. Instead, recycle it by taking it to 2
place that collects used oil. If you have a problem
properly disposing
of your used oil, ask your dealer, a
service station or a local recycling center for help.
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Air Cleaner
As you face the front of the vehicle, the air cleaner is in
the front right section of the engine compartment. There
is a filter inside the air cleaner.
Refer to -the Maintenance Schedule
to detemine when
to replace the air filter.
A I
A CAUTION:
Operating the engine with the air cleaner off can
cause you or others
to be burned. The air
cleaner not only cleans the air,
it stops flame if
I the engine backfires. If it isn’t there, and the
engine backfires, you could be burned. Don’t
drive with
it off, and be careful working on the
engine with the air cleaner off.
I
the air cleaner is off, a backfire can cause a
See “Scheduled Maintenance Services” in the Index.
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Automatic Transaxle Fluid
When to Check and Change:
A good time to check your automatic transaxle fluid
level is when the engine oil is changed. Refer to the
Maintenance Schedule to determine when
to change
your fluid. See “Scheduled Maintenance Services” in
the Index.
How to Check:
Because this operation can be a little difficult, you may
choose to have this done at a Buick dealership Service
Department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading on the
dipstick.

When to Check: Check your tires once a month or
more.
Don’t forget your compact spare tire. It should be at
60
psi (420 kPa).
I
How to Check: Use a good quality pocket-type gage to
check tire pressure. Simply looking at the tires will not
tell you the pressure, especially
if you have radial tires --
which may look properly inflated even if they’re
underinflated.
If your tires have valve caps, be sure to put them back on. They help prevent leaks .by keeping out dirt and
moisture.
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.
r-
Use this rotation pattern.
After the tires have been rotated, adjust the front and
rear inflation pressure
as shown on the Tire-Loading
Information label. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque”
in the
Index.

Buying New .Tires
To find out what kind and size of tires you need, look at
:the Tire-Loading Information 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 a
“MS’,
(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 rdnge, speed rating and construction type (bias,
bias-belted or radial) as your original tires.
, A CAUTION:
Mixing tires could cause you to lose control
while driving.
If you mix tires of different sizes
or types (radial and ‘bias-belted tires), the
1 vehicle may not handle properly, and you cou’ ’
have a crash. Be sure to use the same size ana
type tires on all four wheels.
It’s
all right to drive with your compact spa
though. It was developed for use
on your
vehicle.
~1
Uniform Tire Quality Grading
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles~ sold.in the United States.)
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
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(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 - A, B, C
The traction grades, from highest to lowest are: A, B,
and C. They 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 braking (straight-ahead) traction tests and does not
include cornering (turning) traction.
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
whicrall 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
I
excessive loading, either separately or in combination, !
can cause heat buildup and possible tire failure.
Those grade
b are molded on the sidewalls of passenger
car tires.
While the tires available as standard or optional
equipment on General Motors vehicles may vary with
respect to these grades, all such tires meet General
Motors performance standards and have been approved
for use
on General Motors vehicles. All passenger type
(P Metric) tires must conform to Federal safety
requirements in addition to these grades.
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Weatherstrips
-These are places where glass or metal meets rubber.
Silicone grease there will make them last longer, seal
better, and not squeak. Apply silicone grease with a
clean cloth at least every six months.
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.
-Foreign Material
Calcium chloride and other salts, ice melting agents,
road oil and tar, tree sap, bird droppings, chemicals from industrial chimneys, and other foreign matter can
damage your vehicle’s finish if they remain on painted
surfaces. Use cleaners that are marked safe for painted
surfaces for these stains.
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 fi-om 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 with 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 vehicle washing system
can do this for you.

Vehicle Identification Number (VIN) Service Parts Identification Label
.I You'll find this label on the spare tire cover. It's very
helpful if you ever need to order parts. On this label is:
1111 1111111 IIII 11ll1l11III'1ll1I 1l11IIIl11l11111l111111llIII I IHII1II I 0 Your VIN.
I Its model designation.
ENG'INE Ai3 7 ASSEMBLY ' 0 Paint information.
CODE MOlDEL YEAR PLANT 0 A list of all productibn options and special
equipment.
This
is the legal identifier for your Buick. 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 Add-on Electrical Equipment
windshield from outside your vehicle. The VIN also Be
sure that this label is not removed from the vehicle.
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