Uniform Tire Quality Grading System (UTQGS)
This information relates to the tire grading system developed by the U.S. National Highway
Traffic Safety Administration for grading tires by tread wear, traction, and temperature
performance.
▼ Tr e a d We a r
The 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 cour se.
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 condi tions of their use, however,
and may depart significantly from the norm because of variation s in driving habits, service
practices and differences in ro ad characteristics and climate.
▼Traction-AA, A, B, C
The 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 hi
ghest), B, and C, represent the tire's resistance to the
generation of heat and its ability to dissipate heat when teste d 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 labo ratory test wheel than the minimum required by law.
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P215/65R15 95H is an example of a tire size and load index rating. Here is an explanation
of the various components of tha t 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 ins talled 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 either 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 thr ee-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 t ire'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 indicate s how much weight each tire
can support.
H
“H” is the speed rating. The speed rating denotes the maximum s peed for which the use of
the tire is rated.
Letter Rating Speed Rating
Q9 9 m ph
R1 06 m ph
S 112 mph
T 118 mph
U1 24 m ph
H1 30 m ph
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Traction: The traction grades, from highe st to lowest are AA, A, B, and C. The grades
represent the tire's ability to stop on wet pavement as measure d under controlled conditions
on specified government test surfaces of asphalt and concrete. A tire marked C may have
poor traction performance.
Te m p e r a t u r e : The temperature grades are A (the highest), B and C, represent ing the tire's
resistance to the generation of heat and its ability to dissipa te heat when tested under
controlled conditions on a spec ified indoor laboratory test whe el.
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 p laced 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 a ppears on the tire's sidewall.
SERIOUS INJURY MAY RESULT FROM:
EXPLOSION OF TIRE/RIM ASSEMBLY DUE TO IMPROPER MOUNTING-MATCH
TIRE DIAMETER TO RIM D IAMETER; 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.
▼ Information on Temporary Tires
Please refer to the sample below.
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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 o f 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 t wo-digit number indicates the t ire's ratio of height to width.
D
“D” is the tire construction symbol. D indicates “diagonal ply construction”.
16
“16” is the wheel rim diameter in inches.
90
“90” is the Load Index. This two-or three-digit number indicate s how much weight each tire
can support.
M
“M” is the speed rating. The speed rating denotes the maximum s peed for which the use of
the tire is rated.
Letter Rating Speed Rating
M8 1 m ph
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▼Glossary of Terms
Tire Placard:
A label indicating the OE tire sizes, recommended inflation pr essure, 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 amo unt 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 fr ont 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 kilogram s in excess of the standard items which they replace, and
not previously considered in the curb weight or accessory weigh t, including heavy duty
brakes, ride levelers, roof rack, heavy duty battery, and speci al trim.
Rim is the metal support (wheel) fo r a tire or a tire and tube assembly upon which the tire
beads are seated.
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Tire Maintenance
Improper or inadequate vehicle maintenance can cause tires to w ear abnormally. Here are
some important maintenance points:
▼ Tire Inflation Pressure
Inspect all tire pressu
re monthly (including the spare) when th e tires are cold. Maintain
recommended pressures for the best ride, top handling, and mini mum tire wear. Use the
pressures specified on the vehicle tire information placard or tire label for optimum service.
▼Tire Rotation
To 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 d istribute wear more evenly.
Do not include (TEMPORARY 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 (pa ge 9-9) and inspect the lug nuts
for tightness.
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.
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(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
WA R N I N G
Always use tires that are in good condition:
Driving with worn tires is dangerous. Reduce
d braking, steering, and traction could result in
an accident.
If a tire wears evenly, a wear i ndicator will appear as a solid band across the tread.
Replace the tire when this happens.
New tread Tread wear indicator
Worn tread
You should replace the tire before the band crosses the entire tread.
NOTE
Tires degrade over time, even when they are not being used on the road. It is recommended
that tires generally be replaced when they are 6 years or older. Heat caused by hot climates
or frequent high loading conditions can accelerate the aging process. The period in which
the tire was manufactured (both week and year) is indicated by a 4-digit number.
Refer to Tire Labeling on page 8-25.
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▼Dimensions
U.S.A. and Canada
Item Vehicle specification
Soft top model Hardtop model
Overall length 3,915 mm (154.1 in) 3,915 mm (154.1 in)
Overall width 1,735 mm (68.3 in) 1,735 mm (68.3 in)
Overall height 16 inch wheel vehicle 1,235 mm (48.6 in)
―
17 inch wheel vehicle 1,240 mm (48.8 in) 1,245 mm (49.0 in)
Front tread 1,496 mm (58.9 in) 1,496 mm (58.9 in)
Rear tread 1,503 mm (59.2 in) 1,503 mm (59.2 in)
Wheelbase 2,310 mm (90.9 in) 2,310 mm (90.9 in)
Mexico
ItemVehicle specification
Soft top model Hardtop model
Overall length 3,915 mm (154.1 in) 3,915 mm (154.1 in)
Overall width 1,735 mm (68.3 in) 1,735 mm (68.3 in)
Overall height 1,230 mm (48.4 in) 1,235 mm (48.6 in)
Front tread 1,496 mm (58.9 in) 1,496 mm (58.9 in)
Rear tread 1,503 mm (59.2 in) 1,503 mm (59.2 in)
Wheelbase 2,310 mm (90.9 in) 2,310 mm (90.9 in)
Specifications
Specifications
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