
Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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Driving and Operating 237
Towing Equipment
Hitches
Always use the correct hitch
equipment for your vehicle.
Crosswinds, large trucks going by,
and rough roads can affect the
trailer and the hitch.
Never attach rental hitches or other
bumper-type hitches. Only use
frame-mounted hitches that do not
attach to the bumper.
Always seal any holes in your
vehicle if the trailer hitch removed.
If not sealed, dirt, water, and carbon
monoxide (CO) from the exhaust
may enter your vehicle. SeeEngine
Exhaust 0193.
Consider using mechanical sway
controls with any trailer. Ask a
trailering professional about sway
controls or refer to the trailer
manufacturer's recommendations
and instructions.
Tires
. Do not tow a trailer while using a
compact spare tire on the
vehicle.
. Tires must be properly inflated to
support loads while towing a
trailer. See Tires0274 for
instructions on proper tire
inflation.
Safety Chains
Always attach chains between the
vehicle and the trailer, and attach
the chains to the holes on the trailer
hitch platform. Instructions about
safety chains may be provided by
the hitch manufacturer or by the
trailer manufacturer.
Cross the safety chains under the
tongue of the trailer to help prevent
the tongue from contacting the road
if it becomes separated from the
hitch. Always leave just enough
slack so the combination can turn.
Never allow safety chains to drag on
the ground.
Trailer Brakes
State or local regulations may
require trailers to have their own
braking system if the loaded weight
of the trailer exceeds certain
minimums that can vary from state
to state. Read and follow the
instructions for the trailer brakes so
they are installed, adjusted, and
maintained properly. Never attempt
to tap into your vehicle's hydraulic
brake system. If you do, both the
vehicle anti-lock brakes and the
trailer brakes may not function,
which could result in a crash.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument

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238 Driving and Operating
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.Overloading is another leading
cause of trailer tire blow-outs. Never
load your trailer with more weight
than the tires are designed to
support. The load rating is located
on the trailer tire sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default
trailer tire speed rating is 105 km/h
(65 mph).
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See
Malfunction
Indicator Lamp (Check Engine
Light) 0133. A device connected
to the DLC —such as an
aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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240 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 241
California Proposition65 Warning . . . . . . . . . . . . . . . . . 241
California Perchlorate Materials Requirements . . . . . 242
Accessories and Modifications . . . . . . . . . . . . . . . . 242
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 242
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 243
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 244
Engine Oil . . . . . . . . . . . . . . . . . . . . 247
Engine Oil Life System . . . . . . . 249
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 250
Engine Air Cleaner/Filter . . . . . . 251
Cooling System . . . . . . . . . . . . . . 252
Engine Overheating . . . . . . . . . . 256
Washer Fluid . . . . . . . . . . . . . . . . . 257
Brakes . . . . . . . . . . . . . . . . . . . . . . . 258
Brake Fluid . . . . . . . . . . . . . . . . . . . 259
Battery - North America . . . . . . 260
All-Wheel Drive . . . . . . . . . . . . . . . 261 Starter Switch Check . . . . . . . . . 261
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 261
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 261
Wiper Blade Replacement . . . . 262
Windshield Replacement . . . . . 263
Gas Strut(s) . . . . . . . . . . . . . . . . . . 263
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 264
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 265
Halogen Bulbs . . . . . . . . . . . . . . . . 265
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 265
Headlamps . . . . . . . . . . . . . . . . . . . 265
Fog Lamps . . . . . . . . . . . . . . . . . . . 266
Front Turn Signal Lamps . . . . . 266
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 266
Electrical System
Electrical System Overload . . . 267
Fuses and Circuit Breakers . . . 268
Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 268 Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 272
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 274
All-Season Tires . . . . . . . . . . . . . . 275
Winter Tires . . . . . . . . . . . . . . . . . . 275
Low-Profile Tires . . . . . . . . . . . . . 275
Tire Sidewall Labeling . . . . . . . . 276
Tire Designations . . . . . . . . . . . . . 278
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 278
Tire Pressure . . . . . . . . . . . . . . . . . 281
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 282
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 283
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 284
Tire Inspection . . . . . . . . . . . . . . . . 287
Tire Rotation . . . . . . . . . . . . . . . . . 287
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 288
Buying New Tires . . . . . . . . . . . . . 289
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 290
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 291
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 292
Wheel Replacement . . . . . . . . . . 293

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258 Vehicle Care
Caution (Continued)
.Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or can be heard all the time when the
vehicle is moving, except when
applying the brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated, inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications. See
Capacities and
Specifications 0344.
Brake pads should be replaced as
complete sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or if parts are improperly
installed.

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274 Vehicle Care
Wheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much
flexing. There could be a
blowout and a serious
crash. SeeVehicle Load
Limits 0183.
(Continued)
Warning (Continued)
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are
more likely to be cut,
punctured, or broken by
a sudden impact —such
as when hitting a pothole.
Keep tires at the
recommended pressure.
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
(Continued)
Warning (Continued)
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires.
.Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.
See Tire Pressure for
High-Speed Operation 0282 for
inflation pressure adjustment for
high-speed driving.

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Vehicle Care 275
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 0275.
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 0289.
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)

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276 Vehicle Care
Caution (Continued)
when possible, avoid contact with
curbs, potholes, and other road
hazards.
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P-Metric) Tire Example
(1) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section.
(2) 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.
(3) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with the
U.S. Department of
Transportation Motor Vehicle
Safety Standards.
DOT Tire Date of
Manufacture
:The last four
digits of the TIN indicate the tire
manufactured date. The first two
digits represent the week (01–
52) and the last two digits, the
year. For example, the third
week of the year 2010 would
have a four-digit DOT date
of 0310.
(4) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code are the

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Vehicle Care 277
Tire Identification Number (TIN).
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(5) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(6) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
see Uniform Tire Quality
Grading 0291.
(7) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load.
Compact Spare Tire Example
(1) Tire Ply Material:The type
of cord and number of plies in
the sidewall and under the tread.
(2) Temporary Use Only
:The
compact spare tire or temporary
use tire should not be driven at
speeds over 80 km/h (50 mph).
The compact spare tire is for
emergency use when a regular
road tire has lost air and gone
flat. If the vehicle has a compact
spare tire, see Compact Spare
Tire 0314 andIf a Tire Goes
Flat 0294. (3) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code are the
Tire Identification Number (TIN).
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(4) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load.
(5) Tire Inflation
:The
temporary use tire or compact
spare tire should be inflated to
420 kPa (60 psi). For more
information on tire pressure and
inflation see Tire Pressure
0 281.