wheel size BUICK REGAL 2020 Owners Manual

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
Seats and Restraints 71
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properly
turning off the passenger airbag(s).
SeePassenger Sensing System
0 65.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires
and Wheels 0282 for additional
important information.
If the vehicle must be modified
because you have a disability and
have questions about whether the
modifications will affect the vehicle's
airbag system, or if you have
questions about whether the airbag
system will be affected if the vehicle
is modified for any other reason, call
Customer Assistance. See
Customer Assistance Offices 0342.Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light 0118.
Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, see Where Are the
Airbags? 061. See your dealer
for service.
Replacing Airbag System
Parts after a Crash
{Warning
A crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not properly protect you and your
passenger(s) in a crash, resulting
in serious injury or even death. To
help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.
If an airbag inflates, you will need to
replace airbag system parts. See
your dealer for service.
If the airbag readiness light stays on
after the vehicle is started or comes
on when you are driving, the airbag
system may not work properly. Have
the vehicle serviced right away. See
Airbag Readiness Light 0118.

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
164 Driving and Operating
Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 220
Trailer Towing
General Towing Information(Hatchback Models) . . . . . . . . . 221
General Towing Information (Station Wagon Models) . . . . . 221
Driving Characteristics and Towing Tips . . . . . . . . . . . . . . . . . 221
Trailer Towing . . . . . . . . . . . . . . . . 225
Towing Equipment . . . . . . . . . . . . 227
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . 229
Driving Information
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible:
. Set the climate controls to the
desired temperature after the
engine is started, or turn them
off when not required.
. Avoid fast starts and accelerate
smoothly.
. Brake gradually and avoid
abrupt stops.
. Avoid idling the engine for long
periods of time.
. When road and weather
conditions are appropriate, use
cruise control.
. Always follow posted speed
limits or drive more slowly when
conditions require.
. Keep vehicle tires properly
inflated. .
Combine several trips into a
single trip.
. Replace the vehicle's tires with
the same TPC Spec number
molded into the tire's sidewall
near the size.
. Follow recommended scheduled
maintenance.
Distracted Driving
Distraction comes in many forms
and can take your focus from the
task of driving. Exercise good
judgment and do not let other
activities divert your attention away
from the road. Many local
governments have enacted laws
regarding driver distraction. Become
familiar with the local laws in
your area.
To avoid distracted driving, keep
your eyes on the road, keep your
hands on the steering wheel, and
focus your attention on driving.

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
Driving and Operating 187
DSC allows you to shift an
automatic transmission similar to a
manual transmission. To use the
DSC feature:1. Move the shift lever to the left from D (Drive) into the side
gate marked with (+) and (−).
2. Move the shift lever forward to upshift or rearward to
downshift.
While using the DSC feature, the
vehicle will have firmer, quicker
shifting. You can use this for sport
driving or when climbing or descending hills, to stay in gear
longer, or to downshift for more
power or engine braking.
The transmission will only allow you
to shift into gears appropriate for the
vehicle speed and engine
revolutions per minute (rpm):
.
The transmission will not allow
shifting to the next higher gear if
the vehicle speed or engine rpm
is too low.
. The transmission will not allow
shifting to the next lower gear if
the vehicle speed or engine rpm
is too high.
While in the DSC mode, the
transmission will automatically
downshift when the vehicle comes
to a stop. This will allow for more
power during take-off.
When accelerating the vehicle from
a stop in snowy and icy conditions,
you may want to shift into second
gear. A higher gear allows the
vehicle to gain more traction on
slippery surfaces. Vehicles with a
turbocharged engine may also start
in third gear.
Drive Systems
All-Wheel Drive
If equipped, this feature transfers
torque to the rear wheels as
required. It is fully automatic, and
adjusts itself as needed for road
conditions.
All-Wheel Drive (AWD) performance
is automatically reduced when you
use the compact spare. To restore
full AWD performance, and prevent
excessive wear to the clutch in the
AWD system, replace the compact
spare tire with a full-size tire as
soon as possible. See Compact
Spare Tire 0305.

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
230 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 231
California Proposition65 Warning . . . . . . . . . . . . . . . . . 231
California Perchlorate Materials Requirements . . . . . 232
Accessories and Modifications . . . . . . . . . . . . . . . . 232
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 232
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 233
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 235
Engine Oil . . . . . . . . . . . . . . . . . . . . 238
Engine Oil Life System . . . . . . . 240
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 241
Engine Air Cleaner/Filter . . . . . . 242
Cooling System . . . . . . . . . . . . . . 243
Engine Overheating . . . . . . . . . . 247
Washer Fluid . . . . . . . . . . . . . . . . . 248
Brakes . . . . . . . . . . . . . . . . . . . . . . . 249
Brake Fluid . . . . . . . . . . . . . . . . . . . 250
Battery - North America . . . . . . 251
All-Wheel Drive . . . . . . . . . . . . . . . 252 Starter Switch Check . . . . . . . . . 252
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 252
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 252
Wiper Blade Replacement . . . . 253
Windshield Replacement . . . . . 254
Gas Strut(s) . . . . . . . . . . . . . . . . . . 254
Headlamp Aiming
Front Headlamp Aiming . . . . . . 255
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 256
Halogen Bulbs . . . . . . . . . . . . . . . . 256
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 256
LED Lighting . . . . . . . . . . . . . . . . . 256
Headlamps . . . . . . . . . . . . . . . . . . . 256
Fog Lamps . . . . . . . . . . . . . . . . . . . 257
Front Turn Signal Lamps . . . . . 257
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 257
Electrical System
Electrical System Overload . . . 258
Fuses and Circuit Breakers . . . 259
Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 259 Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 263
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 265
All-Season Tires . . . . . . . . . . . . . . 266
Winter Tires . . . . . . . . . . . . . . . . . . 266
Low-Profile Tires . . . . . . . . . . . . . 266
Tire Sidewall Labeling . . . . . . . . 267
Tire Designations . . . . . . . . . . . . . 269
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 269
Tire Pressure . . . . . . . . . . . . . . . . . 272
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 273
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 274
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 275
Tire Inspection . . . . . . . . . . . . . . . . 278
Tire Rotation . . . . . . . . . . . . . . . . . 279
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 280
Buying New Tires . . . . . . . . . . . . . 280
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 282
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 282
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 284
Wheel Replacement . . . . . . . . . . 284

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
266 Vehicle Care
All-Season Tires
This vehicle may come with
all-season tires. These tires are
designed to provide good overall
performance on most road surfaces
and weather conditions. Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. Original
equipment all-season tires can be
identified by the last two characters
of this TPC code, which will
be“MS.”
Consider installing winter tires on
the vehicle if frequent driving on
snow or ice-covered roads is
expected. All-season tires provide
adequate performance for most
winter driving conditions, but they
may not offer the same level of
traction or performance as winter
tires on snow or ice-covered roads.
See Winter Tires 0266.
Winter Tires
This vehicle was not originally
equipped with winter tires. Winter
tires are designed for increased
traction on snow and ice-covered
roads. Consider installing winter
tires on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your dealer
for details regarding winter tire
availability and proper tire selection.
Also, see Buying New Tires 0280.
With winter tires, there may be
decreased dry road traction,
increased road noise, and shorter
tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
. Use tires of the same brand and
tread type on all four wheel
positions.
. Use only radial ply tires of the
same size, load range, and
speed rating as the original
equipment tires. Winter tires with the same speed
rating as the original equipment tires
may not be available for H, V, W, Y,
and ZR speed rated tires. If winter
tires with a lower speed rating are
chosen, never exceed the tire's
maximum speed capability.
Low-Profile Tires
If the vehicle has 245/45R18 or
245/40R19 size tires, they are
classified as low-profile tires.
Caution
Low-profile tires are more
susceptible to damage from road
hazards or curb impact than
standard profile tires. Tire and/or
wheel assembly damage can
occur when coming into contact
with road hazards like potholes,
or sharp edged objects, or when
sliding into a curb. The warranty
does not cover this type of
damage. Keep tires set to the
correct inflation pressure and (Continued)

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
Vehicle Care 269
(6) Tire Size:A combination of
letters and numbers define a
tire's width, height, aspect ratio,
construction type, and service
description. The letter “T”as the
first character in the tire size
means the tire is for temporary
use only.
(7) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
Tire Designations
Tire Size
The example shows a typical
passenger vehicle tire size.
(1) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter “P”as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.
(2) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item (3) of the illustration, it
would mean that the tire's
sidewall is 60 percent as high as
it is wide. (4) Construction Code
:A letter
code is used to indicate the type
of ply construction in the tire.
The letter “R”means radial ply
construction; the letter “D”
means diagonal or bias ply
construction.
(5) Rim Diameter
:Diameter of
the wheel in inches.
(6) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
278 Vehicle Care
be turned on and off through
the Options menu. SeeDriver
Information Center (DIC) 0128.
4. Use the DIC controls on the right side of the steering wheel
to scroll to the Tire Pressure
screen under the DIC
info page.
5. Press and hold
Vin the center
of the DIC controls.
The horn sounds twice to
signal the receiver is in relearn
mode and the TIRE
LEARNING ACTIVE message
displays on the DIC screen.
6. Start with the driver side front tire.
7. Place the relearn tool against the tire sidewall, near the valve
stem. Then press the button to
activate the TPMS sensor.
A horn chirp confirms that the
sensor identification code has
been matched to this tire and
wheel position. 8. Proceed to the passenger side
front tire, and repeat the
procedure in Step 7.
9. Proceed to the passenger side rear tire, and repeat the
procedure in Step 7.
10. Proceed to the driver side rear tire, and repeat the procedure
in Step 7. The horn sounds two
times to indicate the sensor
identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
11. Turn the vehicle off.
12. Set all four tires to the recommended air pressure
level as indicated on the Tire
and Loading Information label.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected
for signs of wear or damage at
least once a month.
Replace the tire if:
.The indicators at three or
more places around the tire
can be seen.
.There is 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 cannot
be repaired well because of
the size or location of the
damage.

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
Vehicle Care 281
GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of the
vehicle, including brake system
performance, ride and handling,
traction control, and tire
pressure monitoring
performance. GM's TPC Spec
number is molded onto the tire's
sidewall near the tire size. If the
tires have an all-season tread
design, the TPC Spec number
will be followed by MS for mud
and snow. SeeTire Sidewall
Labeling 0267.
GM recommends replacing worn
tires in complete sets of four.
Uniform tread depth on all tires
will help to maintain the
performance of the vehicle.
Braking and handling
performance may be adversely affected if all the tires are not
replaced at the same time.
If proper rotation and
maintenance have been done,
all four tires should wear out at
about the same time. See
Tire
Rotation 0279. However, if it is
necessary to replace only one
axle set of worn tires, place the
new tires on the rear axle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H,
V, W, Y and ZR speed rated
tires. Never exceed the winter
tires’ maximum speed capability
when using winter tires with a
lower speed rating.
{Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
(Continued)
Warning (Continued)
Only your dealer or authorized
tire service center should
mount or dismount the tires.
{Warning
Mixing tires of different sizes,
tread patterns, or types on the
same axle may cause loss of
control of the vehicle, resulting
in a crash or other vehicle
damage. Use the same size,
load range, and type of tires
as the original tires.
{Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
(Continued)

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
282 Vehicle Care
Warning (Continued)
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System 0274.
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. See Vehicle Load Limits
0 171.Different Size Tires and
Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
(Continued)
Warning (Continued)
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires 0280 and
Accessories and Modifications
0 232.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires,

Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada-13557849) -
2020 - CRC - 6/25/19
Vehicle Care 285
Used Replacement Wheels
{Warning
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{Warning
If the vehicle has 245/45R18 or
245/40R19 size tires, do not use
tire chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage
to the brakes, suspension,
or other vehicle parts. The area
damaged by the tire chains could(Continued)
Warning (Continued)
cause loss of control and a crash.
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and road
conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels. If
traction devices are used, install
them on the front tires.
Caution
If the vehicle is equipped with a
tire size other than 245/45R18 or
245/40R19, use tire chains only
where legal and only when
necessary. Use low profile chains
that add no more than 12 mm
thickness to the tire tread and
(Continued)
Caution (Continued)
inner sidewall. Use chains that
are the proper size for the tires.
Install them on the tires of the
front axle. Do not use chains on
the tires of the rear axle. Tighten
them as tightly as possible with
the ends securely fastened. Drive
slowly and follow the chain
manufacturer's instructions. If the
chains contact the vehicle, stop
and retighten them. If the contact
continues, slow down until it
stops. Driving too fast or spinning
the wheels with chains on will
damage the vehicle.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. See Tires
0 265. If air goes out of a tire, it is
much more likely to leak out slowly.
But if there is ever a blowout, here
are a few tips about what to expect
and what to do: