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Tire Information (U.S.A.)
P215/65R15 95H 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 rating. Note that the tire size and
load index rating may be different from the example.
P
Indicates a tire that may be installed on cars, SUVs, minivans and light trucks as designated
by the Tire and Rim Association (T&RA).
NOTE
If your tire size does not begin with a letter this may mean it is designated by ei\
ther ETRTO
(European Tire and Rim Technical Organization) or JATMA (Japan Tire Manufacturing
Association).
215
“215” 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.
65
“65” is the aspect ratio. This two-digit number indicates the tire's ratio of height to width.
R
“R” is the tire construction symbol. R indicates “Radial ply co\
nstruction”.
15
“15” is the wheel rim diameter in inches.
95
“95” is the Load Index. This two-or three-digit number indicates how much weight each tire
can support.
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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 RatingSpeed Rating
Q99 mph
R106 mph
S112 mph
T118 mph
U124 mph
H130 mph
V149 mph
W168* mph
Y186* mph
* For tires with a maximum speed capability over 149 mph, tire manufactur\
ers sometimes
use the letters ZR. For tires with a maximum speed capability over 186 m\
ph, tire
manufacturers always use the letters ZR.
M S or M/S: Mud and Snow
AT: All Terrain.
AS: All Season. The “MS” 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 examp\
le, 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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Tire Information (U.S.A.)
Maximum Permissible Inflation Pressure
This number is the greatest amount of air pressure that should ever be p\
ut 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 t\
he tire
when tested under controlled conditions on a specified government 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 c\
ontrolled 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 wheel.
Snow Tires
In some heavy snow areas, local governments may require true snow tires,\
those with very
deeply cut tread. These tires should only be used in pairs or placed on all four wheels. M\
ake
sure you purchase snow tires that are the same size and construction typ\
e 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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Tire Information (U.S.A.)
Information on Temporary Tires
Please 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 rating. 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 gener\
al, 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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Tire Information (U.S.A.)
16
“16” is the wheel rim diameter in inches.
90
“90” is the Load Index. This two-or three-digit number indicates how much weight each tire
can support.
M
“M” is the speed rating. The speed rating denotes the maximum speed for which the use of
the tire is rated.
Letter RatingSpeed Rating
M81 mph
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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 Pressure
On the tire label you will find the recommended tire inflation pressure in both kPa and
psi for the tires installed as original equipment on the vehicle. 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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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 Pressure
1. 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 stem 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, crac\
ks or other
irregularities.
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Tire Information (U.S.A.)
Glossary of Terms
Tire Placard: A label indicating the OE tire sizes, recommended inflation pressure, and the
maximum weight the vehicle can carry.
Tire Identification Number (TIN): A number on the sidewall of each tire providing
information about the tire brand and manufacturing plant, tire size, and\
date of manufacture.
Inflation Pressure: A measure of the amount of air in a tire.
kPa: Kilopascal, the metric unit for air pressure.
psi: Pounds per square inch, the English unit for air pressure.
B-pillar: The structural member at the side of the vehicle behind the front door.
Original Equipment (OE): Describes components originally equipped on the vehicle.
Vehicle Load Limit: The maximum value of the combination weight of occupants and
cargo.
Bead Area of the Tire: Area of the tire next to the rim.
Sidewall Area of the Tire: Area between the bead area and the tread.
Tread Area of the Tire: Area on the perimeter of the tire that contacts the road when it's
mounted on the vehicle.
Seating capacity means the total allowable number of vehicle occupants. Seating capacity\
is described on the tire label.
Production options weight is the combination weight of installed regular production
options weighing over 2.3 kilograms in excess of the standard items whic\
h they replace,
and not previously considered in the curb weight or accessory weight, in\
cluding heavy duty
brakes, ride levelers, roof rack, heavy duty battery, and special trim.
Rim is the metal support (wheel) for a tire or a tire and tube assembly u\
pon which the tire
beads are seated.
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