
Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
288 Vehicle Care
information on tire pressure and
inflation seeTire
Pressure 0291.
(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 following is an example of 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; and the letter B
means belted-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.

Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
292 Vehicle Care
The Tire and Loading
Information label on the vehicle
indicates the original equipment
tires and the correct cold tire
inflation pressures. The
recommended pressure is the
minimum air pressure needed to
support the vehicle's maximum
load carrying capacity. See
Vehicle Load Limits0199.
How the vehicle is loaded
affects vehicle handling and ride
comfort. Never load the vehicle
with more weight than it was
designed to carry.
When to Check
Check the tires once a month or
more. Do not forget the compact
spare, if the vehicle has one.
The cold compact spare tire
pressure should be at 420 kPa
(60 psi). See Compact Spare
Tire 0310. How to Check
Use a good quality pocket-type
gauge to check tire pressure.
Proper tire inflation cannot be
determined by looking at the tire.
Check the tire inflation pressure
when the tires are cold, meaning
the vehicle has not been driven
for at least three hours or no
more than 1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until the recommended
pressure is reached. If the
inflation pressure is high, press
on the metal stem in the center
of the tire valve to release air.
Recheck the tire pressure with
the tire gauge. Put the valve caps back on the
valve stems to keep out dirt and
moisture and prevent leaks. Use
only valve caps designed for the
vehicle by GM. TPMS sensors
could be damaged and would
not be covered by the vehicle
warranty.
Tire Pressure for
High-Speed Operation
{Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts
additional strain on tires.
Sustained high-speed driving
causes excessive heat buildup
and can cause sudden tire failure.
This could cause a crash, and
you or others could be killed.
Some high-speed rated tires
require inflation pressure
adjustment for high-speed
operation. When speed limits and
road conditions allow the vehicle
(Continued)

Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
300 Vehicle Care
{Warning
Mixing tires of different sizes,
brands, or types may cause
loss of control of the vehicle,
resulting in a crash or other
vehicle damage. Use the
correct size, brand, and type
of tires on all wheels.
{Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
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 0293.
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. See Vehicle Load
Limits 0199.
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, roll bars, 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
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires 0299 and
Accessories and
Modifications 0251.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway

Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
Vehicle Care 303
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.
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
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 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.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. SeeTires
0 283. If air goes out of a tire, it is
much more likely to leak out slowly.
But if there ever is a blowout, here
are a few tips about what to expect
and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible.
A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.

Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
314 Vehicle Care
Towing the Vehicle
Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty.
Do not lash or hook to
suspension components. Use the
proper straps around the tires to
secure the vehicle.
Have the vehicle towed on a wheel
lift tow truck. A flatbed car carrier
could damage the vehicle. The
wheel lift tow truck must raise the
rear of the vehicle and wheel dollies
must be used to lift the front wheels
off the ground.
Consult your dealer or a
professional towing service if the
disabled vehicle must be towed.
Recreational Vehicle
Towing
Recreational vehicle towing means
towing the vehicle behind another
vehicle –such as behind a motor
home. The two most common types
of recreational vehicle towing are
known as dinghy towing and dolly
towing. Dinghy towing is towing the
vehicle with all four wheels on the
ground. Dolly towing is towing the
vehicle with two wheels on the
ground and two wheels up on a
device known as a dolly.
Here are some important things to
consider before recreational vehicle
towing:
. What is the towing capacity of
the towing vehicle? Be sure to
read the tow vehicle
manufacturer's
recommendations.
. How far will the vehicle be
towed? Some vehicles have
restrictions on how far and how
long they can tow. .
Does the vehicle have the
proper towing equipment? See
your dealer or trailering
professional for additional advice
and equipment
recommendations.
. Is the vehicle ready to be
towed? Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.
Caution
Use of a shield mounted in front
of the vehicle grille could restrict
airflow and cause damage to the
transmission. The repairs would
not be covered by the vehicle
warranty. If using a shield, only
use one that attaches to the
towing vehicle.

Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-9921197) -
2017 - crc - 3/30/16
OnStar 359
from each other and use a
combination of letters, numbers,
and symbols to increase the
security.
. Change the default name of the
SSID (Service Set Identifier).
This is your network’s name that
is visible to other wireless
devices. Choose a unique name
and avoid family names or
vehicle descriptions.
OnStar Wi-Fi
®Hotspot (If
Equipped)
The vehicle may have a built-in
Wi-Fi hotspot that provides access
to the Internet and web content at
4G LTE speed. Up to seven mobile
devices can be connected. A data
plan is required. Use the in-vehicle
controls only when it is safe to
do so.
1. To retrieve Wi-Fi hotspot information, press
=, wait for
the prompt, then say “Wi-Fi
settings.” On some vehicles,
touch Wi-Fi Settings on the
screen. 2. The Wi-Fi settings will display
the Wi-Fi hotspot name (SSID),
password, and on some
vehicles, the connection type
(no Internet connection, 3G,
4G, 4G LTE), and signal quality
(poor, good, excellent).
3. To change the SSID or password, press
Qor call
1-888-4ONSTAR to connect
with an Advisor.
After initial set-up, your vehicle’s
Wi-Fi hotspot will connect
automatically to your mobile
devices. Manage data usage by
turning Wi-Fi on or off on your
mobile device, using the
RemoteLink mobile app, or by
contacting an OnStar Advisor.
OnStar RemoteLink
®Mobile App
(If Equipped)
Download the OnStar RemoteLink
mobile app to select Apple
®iOS,
Android™, BlackBerry®,
or Windows®mobile devices.
OnStar Subscribers can access the
following services from a mobile
device: .
Remotely start/stop the vehicle,
if factory-equipped.
. Lock/unlock doors, if equipped
with automatic locks.
. Activate the horn and lamps.
. Check the vehicle’s fuel level, oil
life, or tire pressure,
if factory-equipped with the Tire
Pressure Monitor System.
. Send directions to the vehicle.
. Locate the vehicle on a map
(U.S. market only).
. Turn the vehicle's Wi-Fi hotspot
on/off, manage settings, and
monitor data consumption,
if equipped.
For OnStar RemoteLink information
and compatibility, see
www.onstar.com (U.S.) or
www.onstar.ca (Canada).
Remote Services
Contact an OnStar Advisor to
unlock the doors or sound the horn
and flash the lamps.