tires MAZDA MX5 MIATA 2017 Owner's Guide

8 –22 Customer Information and Reporting Safety Defects
Uniform Tire Quality Grading System (UTQGS)
Uniform Tire Quality Grading System (UTQGS)This information relates to the tire grading system developed b y the U.S. National Highway
Traffic Safety Administration for grading tires by tread wear, traction, and temperature
performance.
Tread WearThe tread wear grade is a comparative rating based on the wear rate of the tire when tested
under controlled conditions on a specified government test cours e.
For example, a tire graded 150 would wear one-and-a-half times as well on the government
course as a tire graded 100.
The relative performance of tires depends upon the actual conditions of their use, however,
and may depart significantly from the norm because of variations in driving habits, service
practices and differences in road characteristics and climate.
Traction-AA, A, B, CThe traction grades, from highest to lowest, are AA, A, B, and C. These grades represent the
tire's ability to stop on wet pavement as measured under contro lled conditions on specified
government test surfaces of asphalt and concrete. A tire marked C may have poor traction
performance.
WARNING The traction grade assigned to this tire is based on braking (straight ahead) traction tests
and does not include acceleration cornering (turning), hydroplaning, or peak traction
characteristics.
Temperature-A, B, C
The temperature grades A (the highest), B, and C, represent the tire's resistance to the
generation of heat and its ability to dissipate heat when tested under controlled conditions on
a specified indoor laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate and reduce tire
life, and excessive temperatures can lead to sudden tire failure.
Grade C corresponds to a level of performance which all passeng er vehicle tires must meet
under the Federal Motor Vehicle Safety Standard No. 109. Grades B and A represent higher
levels of performance on the laboratory test wheel than the min imum required by law.
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8 –23 Customer Information and Reporting Safety Defects
Uniform Tire Quality Grading System (UTQGS)
WARNING Keep your vehicle's tires properly inflated and not overloaded:
Driving with improperly inflated or overloaded tires is dangerous. Excessive speed,
underinflation, or excessive loading, either separately or in combination, can cause heat
buildup and possible tire failure. The temperature grade for this tire is established for a
tire that is properly inflated and not overloaded.
These grades will be added to the sidewalls of passenger vehicle tires over the next several
years according to a schedule established by the NHTSA and the tire manufacturers.
The grade of tires available as standard or optional equipment on Mazda vehicles may vary
with respect to grade.
ALL PASSENGER VEHICLE TIRES MUST CONFORM TO THESE GRADES AND TO
ALL OTHER FEDERAL TIRE-SAFETY REQUIREMENTS.
UNIFORM TIRE QUALITY GRADINGQuality grades can be found where applicable on the tire sidewa ll between tread shoulder
and maximum section width.
For example:
TREADWEAR 200 TRACTION AA TEMPERATURE A UTQGS MARK (example)
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8 –24 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
Tire LabelingFederal law requires tire manufacturers to place standardized i nformation on the sidewall of
all tires. This information identifies and describes the fundamental characteristics of the tire
and also provides a tire identification number for safety standa rd certification and in case of
a recall.
Information on Passenger Vehicle TiresPlease refer to the sample below.
1. TIN: U.S. DOT tire identification number
2. Passenger car tire
3. Nominal width of tire in millimeters
4. Ratio of height to width (aspect ratio)
5. Radial
6. Run-flat tire
7. Rim diameter code
8. Load index & speed symbol
9. Severe snow conditions
10. Tire ply composition and materials used
11. Max. load rating
12. Tread wear, traction and temperature grades
13. Max. permissible inflation pressure
14. SAFETY WARNING
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8 –26 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.) H
“H” is the speed rating. The speed rating denotes the maximum speed for which the use of
the tire is rated. Letter Rating Speed Rating
Q 99 mph
R 106 mph
S 112 mph
T 118 mph
U 124 mph
H 130 mph
V 149 mph
W 168 *
mph
Y 186 *
mph*
For tires with a maximum speed capability over 149 mph, tire m anufacturers sometimes
use the letters ZR. For tires with a maximum speed capability o ver 186 mph, tire
manufacturers always use the letters ZR.
M S or M/S: Mud and Snow
AT: All Terrain.
AS: All Season. The “M
S” or “M/S” indicates that the tire has some functional use in mud
and snow.
U.S. DOT Tire Identification Number (TIN)
This begins with the letters “DOT” which indicates the tire meets all federal standards. The
next two numbers or letters are the plant code where it was manufactured, and the last four
numbers represent the week and year the tire was manufactured. For example, the numbers
457 means the 45st week of 1997. After 2000 the numbers go to four digits. For example,
the number 2102 means the 21th week of 2002. The other numbers are marketing codes
used at the manufacturer's discretion. This information is used to contact consumers if a tire
defect requires a recall.
Tire Ply Composition and Materials Used
The number of plies indicates the number of layers of rubber-coated fabric in the tire.
In general, the greater the number of plies, the more weight a tire can support. Tire
manufacturers also must indicate the tire materials, which include steel, nylon, polyester,
and other.
Maximum Load Rating
This number indicates the maximum load in kilograms and pounds that can be carried by the
tire.
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8 –27 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)Maximum Permissible Inflation Pressure
This number is the greatest amount of air pressure that should ever be put in the tire under
normal driving conditions.
Tread Wear, Traction and Temperature Grades
Tread wear: The tread wear grade is a comparative rating based on the wear rate of the tire
when tested under controlled conditions on a specified governmen t test course. For example,
a tire graded 150 would wear one and one-half (1 1/2) times as well on the government
course as a tire graded 100.
Traction: The traction grades, from highest to lowest are AA, A, B, and C. The grades
represent the tire's ability to stop on wet pavement as measured under controlled conditions
on specified government test surfaces of asphalt and concrete. A tire marked C may have
poor traction performance.
Temperature: The temperature grades are A (the highest), B and C, representing the
tire's resistance to the generation of heat and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory test whee l.
Snow Tires
In some heavy snow areas, local governments may require true sn ow tires, those with very
deeply cut tread. These tires should only be used in pairs or placed on all four wheels. Make
sure you purchase snow tires that are the same size and construction type as the other tires
on your vehicle.
SAFETY WARNING
The following safety warning appears on the tire's sidewall.
SERIOUS INJURY MAY RESULT FROM: 
EXPLOSION OF TIRE/RIM ASSEMBLY DUE TO IMPROPER MOUNTING-MATCH
TIRE DIAMETER TO RIM DIAMETER; NEVER EXCEED 40 psi (275 kPa) TO SEAT
BEADS-ONLY SPECIALLY TRAINED PERSONS SHOULD MOUNT TIRES. 
TIRE FAILURE DUE TO UNDER-INFLATION/OVERLOADING/DAMAGE-
FOLLOW OWNER'S MANUAL AND PLACARD IN VEHICLE-FREQUENTLY
CHECK INFLATION PRESSURE AND INSPECT FOR DAMAGE.
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8 –28 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.) Information on Temporary TiresPlease refer to the sample below.
1. Temporary tires
2. Nominal width of tire in millimeters
3. Ratio of height to width (aspect ratio)
4. Diagonal
5. Rim diameter code
6. Load index & speed symbol
T115/70D16 90M is an example of a tire size and load index rating. Here is an explanation
of the various components of that tire size and load index rati ng. Note that the tire size and
load index rating may be different from the example.
T
Indicates a tire that may be installed on cars, SUVs, minivans and light trucks as designated
by the Tire and Rim Association (T&RA).
11 5
“115” is the nominal width of the tire in millimeters. This three-digit number gives the width
in millimeters of the tire from sidewall edge to sidewall edge. In general, the larger the
number, the wider the tire.
70
“70” is the aspect ratio. This two-digit number indicates the tire's ratio of height to width.
D
“D” is the tire construction symbol. D indicates “diagonal ply construction”.
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8 –30 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
Location of the Tire Label (Placard)You will find the tire label containing tire inflation pressure by tire size and other important
information on the driver's side B-pillar or on the edge of the driver's door frame.
SAMPLE
Recommended Tire Inflation PressureOn the tire label you will find the recommended tire inflation pr essure in both kPa and
psi for the tires installed as original equipment on the vehicl e. It is very important that the
inflation pressure of the tires on your vehicle is maintained at the recommended pressure.
You should check the tire pressure regularly to insure that the proper inflation pressure is
maintained.
Refer to Tires on page 9-8 .
NOTE
Tire pressures listed on the vehicle placard or tire information label indicate the
recommended cold tire inflation pressure, measured when the tires are cold, after the vehicle
has been parked for at least 3 hours. As you drive, the temperature in the tire warms up,
increasing the tire pressure.
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8 –31 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
WARNING Always check the tire inflation pressures on a regular basis according to the
recommended tire inflation pressure on the tire label and in conjunction with the
information in this owner's manual:
Driving your vehicle with under-inflated tires is dangerous.
Under-inflation is the most common cause of failures in any kind of tire and may result
in severe cracking, tread separation or “blowout”, with unexpected loss of vehicle
control and increased risk of injury. Under-inflation increases sidewall flexing and
rolling resistance, resulting in heat buildup and internal damage to the tire. It results in
unnecessary tire stress, irregular wear, loss of control and accidents. A tire can lose up to
half of its air pressure and not appear to be flat!
It is impossible to determine whether or not tires are properly inflated just by looking at
them.
Checking Tire Pressure1. When you check the air pressure, make sure the tires are cold — meaning they are not hot
from driving even a mile.
2. Remove the cap from the valve on one tire.
3. Firmly press a tire gauge onto the valve.
4. Add air to achieve recommended air pressure.
5. If you overfill the tire, release air by pushing on the metal st em in the center of the valve.
Then recheck the pressure with your tire gauge.
6. Replace the valve cap.
7. Repeat with each tire, including the spare.
NOTE
Some spare tires require higher inflation pressure.
8. Visually inspect the tires to make sure there are no nails or other objects embedded that
could poke a hole in the tire and cause an air leak.
9. Check the sidewalls to make sure there are no gouges, cuts, bulges, cracks or other
irregularities.
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8 –33 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
Tire MaintenanceImproper or inadequate vehicle maintenance can cause tires to w ear abnormally. Here are
some important maintenance points:
Tire Inflation PressureInspect all tire pressure monthly (including the spare) when the tires are cold. Maintain
recommended pressures for the best ride, top handling, and minimum tire wear. Use the
pressures specified on the vehicle tire information placard or t ire label for optimum service.
Tire RotationTo equalize tread wear, rotate the tires every 12,000 km (7,500 miles) at the latest or sooner
if irregular wear develops. Mazda recommends to rotate every 8,000 km (5,000 miles) to
help increase tire life and distribute wear more evenly.
Do not include (TEMPORAR Y USE ONLY)
spare tire in rotation. Forward
Inspect the tires for uneven wear and damage. Abnormal wear is usually caused by one or a
combination of the following: 
Incorrect tire pressure 
Improper wheel alignment 
Out-of-balance wheel 
Severe braking
After rotation, inflate all tire pressures to specification (page 9-8 ) and inspect the lug
nuts for tightness.
(With tire pressure monitoring system)
After adjusting the tire pressure, initialization of the tire pressure monitoring system is
necessary to make the system operate normally.
Refer to Tire Pressure Monitoring System Initialization on page 4-108 .
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8 –34 Customer Information and Reporting Safety Defects
Tire Information (U.S.A.)
CAUTION Rotate unidirectional tires and radial tires that have an asymmetrical tread pattern or
studs only from front to rear, not from side to side. Tire performance will be weakened if
rotated from side to side.
(With limited-slip differential)
Don't use the following: 
Tires not of the designated size 
Tires of different sizes or types at the same time 
Tires not sufficiently inflated
If these instructions aren't followed, the rotation of the left and right wheels will be
different and will thus apply a constant load on the limited-slip differential.
This will cause a malfunction.
Replacing a Tire
WARNINGAlways use tires that are in good condition:
Driving with worn tires is dangerous. Reduced braking, steering, and traction could result
in an accident.
If a tire wears evenly, a wear indicator will appear as a solid band across the tread.
Replace the tire when this happens.
Ne w tread Tread wear indicator
Worn tread
You should replace the tire before the band crosses the entire tread.
(With tire pressure monitoring system)
After adjusting the tire pressure, initialization of the tire pressure monitoring system is
necessary to make the system operate normally.
Refer to Tire Pressure Monitoring System Initialization on page 4-108 .
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