automatic transmission BUICK ENVISION 2021 User Guide

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
204 Driving and Operating
automatically shift into N (Neutral). Once
the vehicle is stopped, P (Park) can be
selected.
P :This position locks the drive wheels. Use
P (Park) when starting the vehicle to ensure
the vehicle does not move.
{Warning
It is dangerous to get out of the vehicle
if the transmission is not in P (Park) with
the parking brake set. The vehicle
can roll.
Do not leave the vehicle when the engine
is running. If the engine has been left
running, the vehicle can move suddenly.
You or others could be injured. To be
sure the vehicle will not move, even
when on fairly level ground, always set
the parking brake and place the
transmission into P (Park). See Shifting
Into Park 0201 and
Driving Characteristics and Towing Tips
0 243.
This vehicle is equipped with an
electronically controlled transmission. The
R (Reverse) and D (Drive) shift switches are designed to prevent inadvertent shifting out
of P (Park) unless the ignition is on, and the
brake pedal is applied.
When the vehicle is stopped, press ENGINE
START/STOP to turn off the vehicle. The
transmission will shift to P (Park)
automatically.
The vehicle will not shift into P (Park) if it is
moving too fast. Stop the vehicle and shift
into P (Park).
To shift in and out of P (Park), see
Shifting
Into Park 0201 and
Shifting out of Park 0202.
R : Use this gear to back up.
If the vehicle is shifted into R (Reverse)
while the speed is too high, the vehicle will
shift into N (Neutral). Reduce the vehicle
speed and try the shift again.
To shift into R (Reverse): 1. Bring the vehicle to a complete stop.
2. Pull the R (Reverse) switch on the center console.
To shift out of R (Reverse): 1. Bring the vehicle to a complete stop.
2. Shift to the desired gear. At low vehicle speeds, R (Reverse) can be
used to rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission. See
If the
Vehicle Is Stuck 0193.
N : In this position, the engine does not
connect with the wheels. To restart the
engine when the vehicle is already moving,
use N (Neutral) only.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is firmly on
the brake pedal, the vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while the engine is running at
high speed.
Caution
Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may
damage the transmission. The repairs
would not be covered by the vehicle
(Continued)

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
206 Driving and Operating
2. Apply the brake pedal.
3. Open the door.
4. Shift into N (Neutral), then release thebrake pedal.
5. The indicator should continue to show N. If it does not, repeat Steps 2–4.
6. Exit the vehicle and close the door. The vehicle is now ready for the car wash.
7. The vehicle may automatically shift into P (Park) upon re-entry.
Caution
A transmission hot message may display
if the automatic transmission fluid is too
hot. Driving under this condition can
damage the vehicle. Stop and idle the
engine to cool the automatic
transmission fluid. This message clears
when the transmission fluid has cooled
sufficiently.
D : This position is for normal driving.
If more power is needed for passing, press
the accelerator pedal down. If the vehicle is shifted into D (Drive) while
the speed is too high, the transmission will
get ready to engage D (Drive). Reduce the
vehicle speed, then the transmission will
engage D (Drive).
To shift into D (Drive):
1. Bring the vehicle to a complete stop.
2. Pull the D (Drive) switch on the center console.
To shift out of D (Drive): 1. Bring the vehicle to a complete stop.
2. Shift to the desired gear.
Downshifting the transmission in slippery
road conditions could result in skidding. See
“Skidding” underLoss of Control 0190.
Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Manual Mode
Tap Shift
Caution
Driving with the engine at a high rpm
without upshifting while using Tap Shift,
could damage the vehicle. Always upshift
when necessary while using Tap Shift.
Vehicles with Tap Shift have controls on the
back of the steering wheel to manually shift
the automatic transmission.

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
Driving and Operating 207
Permanent Tap Shift Mode
To enter Permanent Tap Shift Mode:1. With the vehicle in D (Drive), press the M (Manual Mode) button.
2. Pull the steering wheel control toward you to shift. Pull the left control to
downshift, and the right control to
upshift.
To exit Permanent Tap Shift Mode, pull the
D (Drive) switch on the center console.
Temporary Tap Manual Shift Mode
To enter Temporary Tap Shift Mode: 1. With the transmission in D (Drive) and not in Permanent Tap Shift Mode, the
Tap Shift controls will activate a
Temporary Tap Shift Mode, allowing the
transmission to be manually shifted.
2. To deactivate, hold the right control briefly. Automatic shifts return after no
manual shifts have been done for seven
to 10 seconds.
While using Tap Shift, the vehicle will have
firmer, quicker shifting. This can be used 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 shifting
into gears appropriate for the vehicle speed
and engine revolutions per minute (rpm).
If shifting is prevented for any reason, the
M or D will flash in the instrument cluster.
The transmission will not automatically shift
to the next higher gear if the engine rpm is
too high. It will only automatically shift to
the next lower gear if the engine rpm is
much too low.
Drive Systems
All-Wheel Drive
Vehicles with this feature can operate in
All-Wheel Drive (AWD) Mode. When the
AWD feature is active, the system transfers
engine power, if required, to all four wheels.
The system is fully automatic and adjusts to
road conditions for improved traction and
control. In FWD Mode engine power is
transferred to the front wheels only, and
the AWD feature is off.
The AWD feature is automatically activated
when certain modes are selected using the
Driver Mode Control switch. When an AWD
mode change is requested the light will
flash briefly while the system is engaging
and the AWD light will be displayed when
the system is active. When a non-AWD
Mode is selected, the light will flash briefly
while the system disengages and a 2WD
light will be displayed when the AWD
system is off. See
Driver Mode Control 0212.
When a compact spare tire is installed on an
AWD vehicle, the system will automatically
detect the compact spare and reduce AWD
performance to protect the system. To
restore AWD operation and prevent
excessive wear on the system, replace the
compact spare with a full-size tire as soon as
possible. See Compact Spare Tire 0301.Brakes
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
ABS performs a system check when the
vehicle is first driven. A momentary motor
or clicking noise may be heard while this
test is going on, and the brake pedal may
move slightly. This is normal.

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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212 Driving and Operating
When HDC is activated, the initial HDC
speed is set to the current driving speed.
It can be increased or decreased by pressing
+RES or–SET on the steering wheel or by
applying the accelerator or brake pedal. This
adjusted speed becomes the new set speed.
HDC will remain enabled between 22 and
60 km/h (14 and 37 mph); however vehicle
speed cannot be set or maintained in this
range. It will automatically disable if the
vehicle speed is above 80 km/h (50 mph) or
above 60 km/h (37 mph) for at least
30 seconds. Press
5again to re-enable HDC.
Driver Mode Control
Driver Mode Control (DMC) allows the driver
to adjust the overall driving experience to
better suit preference by adjusting multiple
subsystems. Driver Mode availability and
affected vehicle subsystems are dependent
upon vehicle trim level, region, and optional
features.
If the vehicle is in Tour Mode or AWD
Mode, it will stay in that mode through
future ignition cycles. If the vehicle is in any
other mode, it will return to Tour Mode
when the vehicle is restarted. When a mode
is selected, an indicator will come on in the
instrument cluster.
Driver Mode Control Switch
To activate each mode, press the MODE
button on the center console.
Tour Mode : Use for normal city and
highway driving to provide a smooth ride.
This setting provides balance between
comfort and handling. This is the standard/
default mode. There is no persistent
indicator in the instrument cluster for
this mode.
AWD Mode : AWD Mode provides drive
torque to all four wheels. Select AWD Mode
to improve traction and control on slippery
road surfaces, such as gravel, sand, wet
pavement, snow, and ice. When in AWD Mode, the AWD Mode indicator light will be
on. For more information on AWD Mode,
see
All-Wheel Drive 0207.
Sport Mode : Use where road conditions or
personal preference demand a more
controlled response.
Sport Mode improves vehicle handling and
acceleration on dry pavement. When active,
Sport Mode modifies steering efforts,
transmission shifting, AWD torque and
suspension tuning, if equipped.
Off-Road Mode : Use this mode for off-road
recreational driving. Off-Road Mode should
be used to improve driving at moderate
speeds, on grass, gravel, dirt, unpaved roads,
or snow-covered roads. The accelerator pedal
is tuned for off-road use. This mode modifies
pedal mapping, AWD, ABS, ESC, and TCS
Performance.
Snow/Ice Mode : Snow/Ice Mode improves
vehicle acceleration on snow and ice covered
roads. When active, Snow/Ice Mode will
adjust acceleration to optimize traction on
slippery surfaces. This can compromise the
acceleration on dry asphalt.

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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244 Driving and Operating
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode SeeManual Mode 0206.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones
that extend out from the back of the vehicle
do not move further back when a trailer is
towed.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See “Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0203.
Towing a trailer requires experience. The
combination of the vehicle and trailer is
longer and not as responsive as the vehicle
itself. Get used to the handling and braking
of the combination by driving on a level
road surface before driving on public roads.
The trailer structure, the tires, and the
brakes must be all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.
Before driving, inspect all trailer hitch parts

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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246 Driving and Operating
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
When parking your vehicle and your trailer
on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into
the curb if facing downhill or into traffic
if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake. 2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of
the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0314. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically that all nuts and bolts on
the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0265.
Trailer Towing
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
(Continued)
Caution (Continued)
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity for
your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades, outside
temperature, dimensions of the front of the
trailer, and how frequently the vehicle is
used to tow a trailer.
When towing a trailer, the combined weight
of the vehicle, vehicle contents, trailer, and
trailer contents must be below all of the
maximum weight ratings for the vehicle,
including:
.GCWR: Gross Combined Weight Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight Rating

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Vehicle Care 253
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 254
California Proposition 65 Warning . . . . . 254
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 254
Accessories and Modifications . . . . . . . . . 254
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 255
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Engine Compartment Overview . . . . . . . . 257
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Engine Oil Life System . . . . . . . . . . . . . . . . 260
Automatic Transmission Fluid . . . . . . . . . 260
Engine Air Filter Life System . . . . . . . . . . . 261
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 261
Cooling System . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Overheating . . . . . . . . . . . . . . . . . . . 265
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Battery - North America . . . . . . . . . . . . . . . 268
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . 269
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Wiper Blade Replacement . . . . . . . . . . . . . 269
Windshield Replacement . . . . . . . . . . . . . . 270
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 272
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 272
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Electrical System
Electrical System Overload . . . . . . . . . . . . . 272
Fuses and Circuit Breakers . . . . . . . . . . . . . 273
Engine Compartment Fuse Block . . . . . . . 273
Instrument Panel Fuse Block . . . . . . . . . . 276
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 279
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 280
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 281
Tire Terminology and Definitions . . . . . . 282
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Tire Pressure Monitor System . . . . . . . . . 286
Tire Pressure Monitor Operation . . . . . . . 287
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 289
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 289
When It Is Time for New Tires . . . . . . . . 290
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 291
Different Size Tires and Wheels . . . . . . . 292
Uniform Tire Quality Grading . . . . . . . . . 293 Wheel Alignment and Tire Balance . . . . 294
Wheel Replacement . . . . . . . . . . . . . . . . . . . 294
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 295
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 296
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 301
Jump Starting
Jump Starting - North America . . . . . . . . 302
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . 304
Recreational Vehicle Towing . . . . . . . . . . . 304
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 305
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 309
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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260 Vehicle Care
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination of
factors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an oil change is indicated can vary
considerably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
When the system has calculated that oil life
has been diminished, it indicates that an oil
change is necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the oil as
soon as possible within the next 1 000 km
(600 mi). It is possible that, if driving under
the best conditions, the oil life system may
indicate that an oil change is not necessary
for up to a year. The engine oil and filter
must be changed at least once a year and
at this time the system must be reset. Your
dealer has trained service people who willperform this work and reset the system.
It is also important to check the oil regularly
over the course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change. To reset the
system:
1. Using the DIC controls on the right side of the steering wheel, display remaining
OIL LIFE on the DIC. See Driver
Information Center (DIC) 0103. When
remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear
on the display.
2. Press the thumbwheel while the Oil Life display is active. When the confirmation
message displays, select YES. The oil life
will change to 100%. Be careful not to reset the oil life display
accidentally at any time other than after
the oil is changed. It cannot be reset
accurately until the next oil change.
The system is reset when the CHANGE
ENGINE OIL SOON message is off.
If the CHANGE ENGINE OIL SOON message
comes back on when the vehicle is started,
the engine oil life system has not been
reset. Repeat the procedure.Automatic Transmission Fluid
A transmission fluid leak is the only reason
for fluid loss. If a leak occurs, take the
vehicle to your dealer and have it repaired
as soon as possible.
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. See Recommended Fluids and
Lubricants 0322.
See your dealer to have the fluid and filter
changed at the intervals.

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Vehicle Care 265
4. Turn the ignition on. SeeIgnition
Positions 0197.
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator and the brake for automatic transmission
vehicles for two seconds, then release.
At the end of the cycle, check the coolant
level in the surge tank and add coolant if it
is low. Turn off the vehicle, allow the
Electronic Control Module (ECM) to go to
sleep, about 2 minutes, and repeat Steps 3-7.
Listen for pump activation and movement of
the control valves while watching the level
of the coolant in the surge tank. If the tank
empties, turn the ignition off, carefully
remove the surge tank cap, refill to the
indicated mark, and repeat Steps 3-6. The fill
and air removal process will run for
approximately 10 minutes.
Engine Overheating
The vehicle has several indicators to warn of
the engine overheating. There is an engine coolant temperature
gauge and an engine coolant temperature
warning light on the instrument cluster. See
Engine Coolant Temperature Gauge
093.
The vehicle may also display a message on
the Driver Information Center (DIC).
If the decision is made not to lift the hood
when this warning appears, get service help
right away.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface. Then check to see if the engine
cooling fan is running. If the engine is
overheating, the fan should be running. If it
is not, do not continue to run the engine.
Have the vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam Is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed with no
sign of steam: 1. Turn the air conditioning off.

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282 Vehicle Care
(2) Tire Width:The 3-digit number
indicates the tire section width in
millimeters from sidewall to sidewall.
(3) Aspect Ratio
:A 2-digit number that
indicates the tire height-to-width
measurements. For example, if the tire
size aspect ratio is 75, as shown in
item (3) of the illustration, it would
mean that the tire's sidewall is
75 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).
Accessory Weight
:The combined
weight of optional accessories. Some
examples of optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship of a
tire's height to its width.
Belt
:A rubber coated layer of cords
between the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that hold
the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which
the plies are laid at alternate angles
less than 90 degrees to the centerline
of the tread. Cold Tire Pressure
:The amount of air
pressure in a tire, measured in kPa
(kilopascal) or psi (pounds per square
inch) before a tire has built up heat
from driving. See Tire Pressure0284.
Curb Weight
:The weight of a motor
vehicle with standard and optional
equipment including the maximum
capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the
sidewall of a tire signifying that the tire
is in compliance with the U.S.
Department of Transportation (DOT)
Motor Vehicle Safety Standards. The
DOT code includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also identify the
tire manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight Rating.
See Vehicle Load Limits 0193.
GAWR FRT
:Gross Axle Weight Rating
for the front axle. See Vehicle Load
Limits 0193.