2003 BUICK REGAL engine

7,500 Miles (12 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
15,000 Miles (25 000 km)
❑Inspect engine air cleanerfilter. If necessary, replace
thefilter. If vehicle is driven in dusty/dirty conditions,
inspectfilter at every engine oil change. See
Engine Air Cleaner/Filter on page 5-18for more
information.An Emission Control Service. (See
footnote†.)
❑Replace passenger compartment airfilter. If you
drive regularly under dusty conditions, thefilter
may require replacement more often.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
22,500 Miles (37 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
30,000 Miles (50 000 km)
❑Replace passenger compartment airfilter. If you
drive regularly under dusty conditions, thefilter
may require replacement more often.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
❑Replace engine air cleanerfilter. SeeEngine Air
Cleaner/Filter on page 5-18for more information.
An Emission Control Service.
❑For supercharged engines only: Check the
supercharger oil level and add the proper
supercharger oil as needed (or every 36 months,
whichever occursfirst). SeePart D: Recommended
Fluids and Lubricants on page 6-16.An Emission
Control Service. (See footnote†.)
37,500 Miles (62 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
6-6
2003 - Regal OM

45,000 Miles (75 000 km)
❑Inspect engine air cleanerfilter. If necessary, replace
thefilter. If vehicle is driven in dusty/dirty conditions,
inspectfilter at every engine oil change. See
Engine Air Cleaner/Filter on page 5-18for more
information.An Emission Control Service. (See
footnote†.)
❑Replace passenger compartment airfilter. If you
drive regularly under dusty conditions, thefilter
may require replacement more often.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
50,000 Miles (83 000 km)
❑Change automatic transaxlefluid andfilter if the
vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change theuid andlter at 100,000 miles
(166 000 km).
52,500 Miles (87 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
60,000 Miles (100 000 km)
❑Replace passenger compartment air lter. If you
drive regularly under dusty conditions, the lter
may require replacement more often.
❑For supercharged engines only: Check the
supercharger oil level and add the proper
supercharger oil as needed (or every 36 months,
whichever occurs rst). SeePart D: Recommended
Fluids and Lubricants on page 6-16.An Emission
Control Service. (See footnote†.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
❑Replace engine air cleaner lter. SeeEngine Air
Cleaner/Filter on page 5-18for more information.
An Emission Control Service.
67,500 Miles (112 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
6-7
2003 - Regal OM

75,000 Miles (125 000 km)
❑Inspect engine air cleanerlter. If necessary, replace
thelter. If vehicle is driven in dusty/dirty conditions,
inspectlter at every engine oil change. See
Engine Air Cleaner/Filter on page 5-18for more
information.An Emission Control Service. (See
footnote†.)
❑Replace passenger compartment airlter. If you
drive regularly under dusty conditions, thelter
may require replacement more often.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
82,500 Miles (137 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
90,000 Miles (150 000 km)
❑Replace passenger compartment airlter. If you
drive regularly under dusty conditions, thelter
may require replacement more often.
❑Replace engine air cleanerlter. SeeEngine Air
Cleaner/Filter on page 5-18for more information.
An Emission Control Service.
❑For supercharged engines only: Check the
supercharger oil level and add the proper
supercharger oil as needed (or every 36 months,
whichever occursrst). SeePart D: Recommended
Fluids and Lubricants on page 6-16.An Emission
Control Service. (See footnote†.)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
97,500 Miles (162 500 km)
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-59for proper rotation pattern and additional
information.(See footnote @.) (See footnote +.)
6-8
2003 - Regal OM

100,000 Miles (166 000 km)
❑Inspect spark plug wires.An Emission Control
Service.
❑Replace spark plugs.An Emission Control Service.
❑Change automatic transaxleuid andlter if the
vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
❑If you haven’t used your vehicle under severe service
conditions listed previously and, therefore, haven’t
changed your automatic transaxleuid, change both
theuid andlter.
150,000 Miles (240 000 km)
❑Drain,ush and rell cooling system (or every
60 months since last service, whichever occursrst).
SeeEngine Coolant on page 5-22for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.An Emission Control Service.
❑Inspect engine accessory drive belt.An Emission
Control Service.
6-9
2003 - Regal OM

Part B: Owner Checks and Services
Listed in this part are owner checks and services
which should be performed at the intervals specied to
help ensure the safety, dependability and emission
control performance of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever anyuids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
in Part D.
At Each Fuel Fill
It is important for you or a service station attendant to
perform these underhood checks at each fuelll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-13for further
details.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-22for further details.
Windshield Washer Fluid Level Check
Check the windshield washeruid level in the windshield
washer tank and add the properuid if necessary.
SeeWindshield Washer Fluid on page 5-38for further
details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inated to the correct pressures.
Don’t forget to check your spare tire. SeeTires on
page 5-56for further details.
Cassette Tape Player Service
Clean cassette tape player. Cleaning should be done
every 50 hours of tape play. SeeAudio System(s)
on page 3-44for further details.
6-10
2003 - Regal OM

Starter Switch Check
{CAUTION:
When you are doing this check, the vehicle
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-24if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
Automatic Transaxle Shift Lock Control
System Check
{CAUTION:
When you are doing this check, the vehicle
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-24if necessary.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don’t start the engine. Without applying
the regular brake, try to move the shift lever out
of PARK (P) with normal effort. If the shift lever
moves out of PARK (P), your vehicle needs service.
6-12
2003 - Regal OM

Ignition Transaxle Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
The key should turn to LOCK only when the
shift lever is in PARK (P).
The key should come out only in LOCK.
Parking Brake and Automatic Transaxle
Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
To check the parking brake’s holding ability: With
the engine running and transaxle in NEUTRAL (N),
slowly remove foot pressure from the regular
brake pedal. Do this until the vehicle is held by the
parking brake only.
To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK (P). Then
release the parking brake followed by the regular
brake.
Underbody Flushing Service
At least every spring, use plain water toush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-13
2003 - Regal OM

Part C: Periodic Maintenance
Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall).You should let your dealer’s
service department do these jobs. Make sure any
necessary repairs are completed at once.
Proper procedures to perform these services may be
found in a service manual. SeeService Publications
Ordering Information on page 7-10.
Steering, Suspension and Front
Drive Axle Boot and Seal Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chang, etc. Clean and then inspect the drive
axle boot seals for damage, tears or leakage. Replace
seals if necessary.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system. Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which
could cause a heat build-up in theoor pan or could let
exhaust fumes into the vehicle. SeeEngine Exhaust
on page 2-29.
6-14
2003 - Regal OM