
BRIDGESTONE / FIRESTONE
42
Speed Rating: The tire’s speed rating is void if the tire is repaired, 
retreaded, damaged, abused, or otherwise altered from its original 
condition. Thereafter, it should be treated as a non-speed rated tire. 
See “Tire Speed Ratings” in this manual.
Improper repair voids the tire Limited Warranty. See “Limited 
Warranty” in this manual.
RFT (Run-Flat Technology) Tires: In addition to the above, there are 
recommendations specific to the repair of RFT tires; see “RFT Tires 
with Run-Flat Technology” in this manual.
Tire Mounting and Other Servicing 
 SAFETY WARNING
Removing and replacing tires on wheels can be dangerous. Attempting 
to mount tires with improper tools or procedures may result in a tire 
explosion causing serious personal injury or death. This is only a job 
for a qualified tire service professional. Never perform tire service 
procedures without proper training, tools, and equipment.
This manual is not intended to provide proper training or service 
procedures for tire mounting, demounting, balancing, rotation, 
or repair. Please leave these tasks to qualified tire service 
professionals. For your safety and that of others:
•
 Always stand well clear of any tire mounting operation. This is 
especially important when the service operator inflates the tire. If 
the tire has been improperly mounted, it may burst with explosive 
force causing serious personal injury or death.
•
 Tires must match the width and diameter requirements of the 
wheels. For example, 16 inch diameter tires must only be mounted 
to 16 inch diameter wheels. Radial tires must only be mounted to 
wheels approved for radial tires.
•
 Wheels must be free of cracks, dents, chips, and rust. Tires must 
be free of bead damage, cuts, and punctures.
•
 Never inflate a tire beyond 40 psi (275 kPa) to seat the beads. Be 
absolutely certain beads are fully seated before adjusting inflation 
pressure to the level recommended for vehicle operation. 

BRIDGESTONE / FIRESTONE
43
• Never put flammable substances in tire/wheel assemblies at 
any time. Never put any flammable substance into a tire/wheel 
assembly and attempt to ignite to seat the beads.
•
 Always stand well away from the work area when tires are being 
spin balanced either on or off the vehicle.
High Performance, Low Aspect Ratio Tires
Many new vehicles come equipped from the factory with high 
performance and/or low aspect ratio tires. Generally, these tires 
provide increased vehicle handling capability, but may also have 
numerous engineering performance trade-offs associated with  
their designs. •
 Low aspect ratio tires, with reduced sidewall height, may be 
more susceptible to damage from potholes, road hazards, and 
other objects such as curbs. This is true for the wheels as well. 
Therefore, as with all other tires, it is important to drive with care 
and maintain proper inflation pressure and load conditions. See 
“Tire Inflation Pressure” and “Tire Damage, Inspection and Service 
Life” in this manual.
•
 Some sports cars and other handling performance enhanced 
vehicles, including sedans and light trucks/SUVs, may be originally 
equipped with high performance tires that are more optimized 
for warmer weather use. Colder, winter weather traction may be 
reduced for these types of tires. Winter tires may be recommended 
by the vehicle manufacturer for colder weather application. See 
“Winter Tires,” the next section in this manual.
•
 High performance tires may also wear more quickly, ride more 
firmly, and produce more noise during operation.
Consult your vehicle owner’s manual and tire information placard, or 
a qualified tire service professional, for more information and specifics 
regarding these types of tires. 

BRIDGESTONE / FIRESTONE
46
Thereafter, it should be treated as a non-speed rated tire.
•
 Non-speed rated tires are usually for ordinary passenger car or 
light truck service and not for high speed driving.
•
 For winter tires used in cold weather conditions, it is generally 
acceptable to apply a tire with a lower speed rating than your 
original tires; however, speed should be reduced accordingly. All 
winter tires should be the same speed rating. Some vehicles have 
specific recommendations regarding winter tire use; consult your 
vehicle owner’s manual and tire information placard. See “Winter 
Tires” in this manual.
These speed ratings are based on standardized laboratory tests 
under specific, controlled conditions. While these tests may relate to 
performance on the road, real-world driving is rarely identical to any 
test conditions. Your tire’s actual speed capability may be less than its 
rated speed since it is affected by factors such as inflation pressure, 
load, tire condition (including damage), wear, vehicle condition 
(including alignment), driving conditions, and duration at which the 
speed is sustained. Use the following chart to compare the speed 
ratings of tires.
Speed  Speed Category*
Symbol   mph                    km/h
M81130
Q 99160
R 106170
S 112180
T 118190
U 124200
H 130210
V 149240
Z** >149 >240
W 168270
Y 186300
(Y)*** >186 >300 

BRIDGESTONE / FIRESTONE
47
The tire’s speed rating designation appears on the tire sidewall with the 
tire size. Examples:
P275/40ZR17
   max > 149 mph (240 km/h)****
P275/40R17
 93W max = 168 mph (270 km/h)
P275/40ZR17
 93W max = 168 mph (270 km/h)
P275/40ZR17
 93Y max = 186 mph (300 km/h)
P275/40ZR17
 93(Y) max > 186 mph (300 km/h) ****
*In standardized laboratory tests that relate to highway speeds.  Actual tire speed and 
performance capability depend on factors such as inflation pressure, load, tire condition, 
wear, and driving conditions.
** Any tire having a maximum speed capability above 149 mph (240 km/h) may, at the 
tire manufacturer’s discretion, include a “Z” in the size designation (i.e. P275/40ZR17).
*** For tires having a maximum speed capability above 186 mph (300 km/h), a “Z”   
must appear in the size designation and a “Y” marked in brackets (as shown) in the 
service description.
**** Consult the tire manufacturer for maximum speed capability.
Tire Spinning
 SAFETY WARNING
Spinning a tire to remove a vehicle stuck in mud, ice, snow, or wet 
grass can be dangerous. A tire spinning at a speedometer reading 
above 35 mph (55 km/h) can in a matter of seconds reach a speed 
capable of disintegrating a tire with explosive force. Under some 
conditions, a tire may be spinning at a speed twice that shown on 
the speedometer. This could cause serious personal injury or death 
to a bystander or passenger. Never spin a tire above a speedometer 
reading of 35 mph (55 km/h).
Radial Tire Rotation
 
The purpose of tire rotation is to minimize irregular or uneven wear 
caused by maintaining a tire in one rotation direction and one position \
over an extended period. Rotate tires as recommended by the vehicle 
manufacturer or every 5,000 miles. Individual tire pressures must 
be checked after rotation and adjusted to the vehicle manufacturer ’s 
recommendation for the tire’s new location on the vehicle. Vehicle 
alignment should be checked if irregular wear is evident. 

BRIDGESTONE / FIRESTONE
49
• To use a full-size spare in the rotation pattern on vehicles with 
dual rear wheels, consult your vehicle owner’s manual for the 
recommended procedures or consult the vehicle manufacturer.
Your Spare Tire
 
Consult your vehicle owner’s manual for proper application of your 
spare tire. Your car may be equipped with a “temporary use” spare tire; 
this spare may differ in size and construction from the other tires on 
your vehicle.
 SAFETY WARNING
Check inflation pressure before use. Failure to have proper inflation 
pressure when using your spare tire can result in serious personal 
injury or death. See “Tire Inflation Pressure” in this manual.
 SAFETY WARNING
Mounting a “temporary use” tire on a wheel which is not specifically 
designed for it, or placing another type tire on a wheel designated 
for temporary use can be dangerous. Your vehicle’s handling 
characteristics can be seriously affected. You could have an accident 
resulting in serious personal injury or death. Consult your vehicle 
owner’s manual for proper application of your “temporary use”   
spare tire.
The spare tire in your vehicle is intended to be used as a spare when 
needed. The spare tire carrier is not intended to be used for long 
term storage, except for “temporary use” tires. If your spare is t\
he 
same size, load rating, and type of tire as your road tires, it should b\
e 
included in the tire rotation process; see “Radial Tire Rotation” in this 
manual for more information.
The spare should be included in regular tire inspections and inflation 
pressure checks. In addition, it should be replaced 10 years after 
date of manufacture, regardless of condition or tread depth. For more 
information, see the “Tire Damage, Inspection and Service Life” in  
this manual. 

BRIDGESTONE / FIRESTONE
51
Tire Registration 
Registration of your tires is an important safety precaution since it 
enables the manufacturer to notify you in the event of a recall. When 
you purchase replacement tires, the retailer will provide a registration\
 
card on which the tire identification numbers have been recorded; 
fill in your name and address on the card and mail it promptly. Some 
retailers may submit the registration for you. You do not need to 
register tires which come as original equipment on new vehicles—the 
vehicle and tire manufacturers handle that for you.
RFT Tires with Run-Flat Technology 
If your vehicle is equipped with Bridgestone or Firestone brand RFT 
tires, this chapter presents specific maintenance and safety issues 
associated with these tires that are in addition to those covered 
elsewhere in this manual.
What is RFT? Run-Flat Technology tires are extraordinary tires that 
utilize specially designed components to temporarily support your 
vehicle in the event of inflation pressure loss, such as from a puncture. 
This gives you the ability to drive to a convenient and safe location 
to change your tire (if equipped with a spare) or have it inspected for 
possible repair or replacement.
Naturally, certain run-flat and low pressure operating limitations   
apply, which varies according to the specific self-supporting tire design. 
Like all tires, during normal operation, they must be properly inflated 
and maintained. Regardless of the design or quality, no tire  
is indestructible.
RFT—How to Identify : Bridgestone and Firestone brand tires  
are marked on the sidewalls, near the wheel, with the RFT logo  
(shown above). 

BRIDGESTONE / FIRESTONE
52
RFT Inflation Pressure 
Like other tires, RFT tires need proper inflation pressure maintenance 
for safe operation and to achieve the maximum  tire life and 
performance. Check inflation pressures monthly and before long 
trips or carrying extra weight. Use an accurate tire gauge and check 
pressures when the tires are cold. Follow the vehicle manufacturer’s 
recommendation for inflation pres- sure settings as indicated on the 
vehicle tire information placard and/or in the vehicle owner’s manual. 
Do not forget the spare, if applicable. See “Tire Inflation Pressure” in 
this manual.
Tire Pressure Monitoring System (TPMS)
A functioning tire pressure monitoring system (TPMS) must be used 
with your RFT tires. Because these tires ride so well even without 
inflation pressure, the TPMS may be necessary to alert you of an 
inflation pressure loss condition. When alerted, follow the instructions 
in your vehicle owner’s manual and see “Run-Flat or Low Tire Pressure 
Operation,” the following section in this manual.
The vehicle or TPMS manufacturer may advise checking the TPMS 
regularly to confirm it is in working order. In addition, a new pressure 
sensor, certain components, or reprogramming may be necessary 
when a tire is serviced. Consult your vehicle owner’s manual, vehicle 
manufacturer, or a Bridgestone Firestone Run-Flat Certified Retailer for 
questions regarding TPMS operation and service.
Run-Flat or Low Tire Pressure Operation
 SAFETY WARNING
Serious personal injury or death may result from a tire failure or 
accident due to improper run-flat or low tire pressure operation. Read 
and follow the instructions below, and the other maintenance and 
safety recommendations elsewhere in this manual.
General Instructions
The Tire Pressure Monitoring System (TPMS) required in your vehicle 
may have different methods of alerting you when your tire has lost 
inflation pressure. The international standard for the definition of run- 

BRIDGESTONE / FIRESTONE
53
flat operation is pressure at or below 10 psi (70 kPa); however, some 
vehicle manufacturers may have established a different pressure 
limit. Consult your vehicle owner’s manual for the details of your 
TPMS. Once the TPMS has indicated that a tire has reduced inflation 
pressure, the run-flat mode of operation has commenced. During this 
phase of operation, please follow these instructions:•
 Reduce speed as much as safely and reasonably possible; do 
not exceed 50 mph (80 km/h). The greater the speed, the less 
distance the tire can travel.
•
 Avoid abrupt or aggressive acceleration, braking, or cornering 
maneuvers as much as safely and reasonably possible. Pot 
holes and other road hazards should be avoided. Careful driving 
limits potential damage to the tire, wheel, and vehicle.
•
 Proceed to a safe and convenient location for tire service 
as soon as possible.  Take note of your mileage; your operation 
distance is limited. See “Distance—How Far You Can Drive,” the 
next section in this manual.
•
 If an unusual vibration or vehicle handling difficulty arises, 
stop driving as soon as safely and reasonably possible.  The 
tire may be about to suddenly fail. Release the accelerator and 
gradually reduce speed. The tire will need to be replaced before 
proceeding.
•
 If towing a trailer, stop driving as soon as safely and 
reasonably possible. In this condition, it is potentially dangerous 
to operate a vehicle/trailer combination. If possible, disconnect the 
trailer and proceed as noted above. Do not continue to tow any 
trailer until proper tire service or replacement has been performed.
•
 Do not touch a tire recently run-low or run-flat (it may be very 
hot). Allow the tire to cool before handling.
Distance—How Far You Can Drive
Factors affecting run-flat or low tire pressure operating distance include 
vehicle speed, load, and maneuvering; the amount of inflation pressure 
loss; the extent of any tire damage; and ambient temperature.
The tire may be marked on the sidewall with run-flat or low tire 
pressure operating speed and/or distance limitations, which vary by tire\