Tire Basics

General Function of Tires for All Types of Vehicles

1. Weight-bearing

Air pressure and tire construction are important factors to carry and sustain the weight of vehicles.

2. Absorb shocks

Air pressure and tire construction reduces initial road vibrations and shocks before being muted again by the suspension.

3. Delivering power from the engine

Tires serve to deliver power from the engine to move the vehicle and also provides traction and braking performance

4. Translating steering wheel movement

Tires are very important in controlling the direction of the vehicle, which will determine the maneuvering capability and stability in driving.

Understand tire size

Tires have its 'language' to communicate in the form of a series of numbers and letters to indicating data specification, brand and type. It is universal and has been agreed by all tire manufacturers worldwide.

Here are the meanings of these codes:

Tire width (in mm)
A tire's aspect ratio is the dimensional relationship of the tire's section height to section width, expressed as a percentage.
Diameter of wheel (in inches)
Load Index
Speed Index

Experience the Performance.

UTQG (Uniform Tire Quality Grades) Rating

The UTQG (Uniform Tire Quality Grades) rating is a labeling requirement by the U.S Department of Transportation for all tire manufacturers. The label of UTQG represents a tire's Treadwear, Traction and Temperature resistance. Traction and temperature resistance ratings are specific performance levels, while treadwear ratings are assigned by manufacturers following tests conducted and are reliable when comparing tires of the same brand.

The UTQG rating comprises of 3 components

Treadwear:

The treadwear grade indicates the wear rate of a tire and is a comparative rating based on test conducted by tire manufacturers. The grades are not an indication of actual mileage, but can be used as a relative comparison. For example, a grading of 400 should last twice as long as a tire graded 200, given similar driving conditions in the same brand.

Traction:

Traction rating is an indication of a tire's ability to stop while on wet pavement. The braking distance is indicated by ratings of "AA" (highest braking ability), "A", "B" and "C". Traction rating only indicates straight line wet braking and does not indicate wet cornering abilities of the tire.

Temperature:

Temperature resistance rating indicates the tire's ability to withstand heat. It is graded according to a properly inflated and not overloaded tire. It is graded from "C", being the lowest, to "B" and "A" ratings.

Understand Load Index and Speed Rating

The Speed index is an assigned letter ranging from J to Z that corresponds to the reference maximum speed at the associated load index. Refer to the load index and speed rating tables below.

These two elements put together are called the service description and are mutually dependent. The table below gives the load index and the speed symbol with their corresponding value.

Load Index (Symbol and maximum load in Lbs & Kg)

LI	Lbs	Kgs	LI	Lbs	Kgs	LI	Lbs	Kgs	LI	Lbs	Kgs
71	761	345	81	1019	462	91	1356	615	101	1819	825
72	783	355	82	1047	475	92	1389	630	102	1874	850
73	805	365	83	1074	487	93	1433	650	103	1929	875
74	827	375	84	1102	500	94	1477	670	104	1984	900
75	853	387	85	1135	515	95	1521	690	105	2039	925
76	882	400	86	1168	530	96	1565	710	106	2094	950
77	908	412	87	1201	545	97	1609	730	107	2149	975
78	937	425	88	1235	560	98	1653	750	108	2205	1000
79	963	437	89	1279	580	99	1709	775	109	2271	1030
80	992	450	90	1323	600	100	1764	800	110	2337	1060

Speed Rating (symbol and maximum speed in MpH & KmH)

Note: A "ZR" may appear for tires having a maximum speed capability above 240km/h (150 mph)

-	J	K	L	M	N	P	Q	R	S	T	H	V	W	Y
MpH	62	68	75	81	87	93	100	113	113	118	130	150	168	188
KmH	100	110	120	130	140	150	160	170	180	190	210	240	270	300

Vehicle Size Close

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What type of fitment do you have?

One Size Fitment Types Square Wheel Fitment When the tires are equal at all four corners, and there is no tire width difference between front and rear axles, the setup is square.

Two Sizes Fitment Types Staggered Fitment When the tires are not equal at all four corners, and there is a tire width difference between front and rear axles, the setup is staggered.

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Section Width Section Width How to find your width? This three-digit number represents the width of the tire in millimeters (mm), measured from sidewall to sidewall. Since this measure is affected by the width of the rim, the measurement is done when the tire is on its intended rim size. Aspect Ratio Aspect Ratio How to find your aspect ratio? The aspect ratio is the relationship of a tire's sidewall height to its section width, expressed as a percentage. In this example, the tire sidewall height is approximately 55% of the tire width. The higher the number, the taller the sidewall; the lower the number, the shorter the sidewall. Rim Diameter Rim Diameter How to find your Rim Diameter? The diameter of the rim in inches.

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