If at some point you feel good enough, catch a car tire, and you'll find up to 3 code snippets printed on it.
In fact, basically, no one cares what that number does. The tire is to fit into the vehicle, and the installation is finished, so drive it away, as long as it does not explode.
Printed letters on tires, meaning the words must mean something.
But people have printed letters on tires, meaning those words must mean something. And if you want to find out, the information they bring is also very interesting. Let's take a few examples and analyze it.
1. Information on size and load index, maximum speed of tires
Basic information printed on tires.
Take the example shown above, and the code sequence is P215 / 65R1598H.
- P: The first "P" means a vehicle tire - Tire Type . "P" here stands for P - Metric, specifying the type of tire for passenger cars such as cars, minivans, pickup trucks and SUVs. In addition you will be able to meet some other symbols such as "ST" (Special Trailer) - tires for cars, boats, multi-purpose trailers or "T" (Temporary Spare) - spare tires. However, it is not always possible to sign a tire type at the top of the range, such as the "LT" sign (Light truck). If it specifies the type of tire used for small trucks such as SUVs, semi-load capacity of 700kg - 1 ton, it will be at the top of the code but if at the end, such as in 9.5-16.5 LT121 / 117R Tire designed for heavy transport trucks.
- 215: That's Tire width (215) - the width is measured from one side of the tire to the other.
- 65: Aspect ratio (65) is the ratio between the height of the tire (measured from the wheel rim to the tread face) with the width of the tire as above. Number 65 means tire wall height equal to 65% of tire width. The lower the number, the shorter the tire wall.
- R: Construction type (R) - symbol of the inner structure of the tire. The letter "R" stands for radial tire, the most popular tire. Also, you may encounter other symbols like "D" which are bias ply or "B" type - tire belted.
- 15: Wheel diameter (15) is the diameter of the tray in inches (1 inch = 2.54 cm). Popularity of this size is always round numbers from 8 to 28, called "inch rim" sizes, common in passenger tires, small-load trucks, minivans and valves.
- But there are also odd numbers like 14.5, 15.5, 16.5, 17.5 and 19.5 (for example, in 33x12.5R16.5 118R). This size is only available in large truck and semi-trailer tires.
- 98: Load index (98) - load index tells us the maximum load that the tire can withstand when fully pumped. Like the upper tire means it can withstand 750kg.
- H : Speed rating (H) - the maximum speed that a vehicle can achieve when the tire has been installed in the vehicle, designated in the form of a letter. As well as the load index, each speed level will correspond to a letter A - Z in increasing magnitude (below table). And note, the speed above is only applied when the tire is completely not broken, slightly steamed or the car is being transported too heavy.
2. DOT code
The second code on the tire also carries extremely important information starting with "DOT" and tire number - TIN (Tire Identification Number). Example: DOT 4B08 4DHR 2910.
DOT stands for Ministry of Transportation, confirming tires that have passed the Ministry's censorship according to motor vehicle safety standards. After DOT is the tire number with the codes.
The first group of codes (4B) with two to three characters may be numbers or letters, the code of the tire factory. The second group of codes (08) with no more than two characters, defines the tire size. The third code group (4DHR) of no more than four characters is an optional code set by the manufacturer according to the size or characteristics of the tire. For consumers, these three groups of codes are not as useful as the last group.
The last group of codes (2910) tells us the tire production time. This four-digit writing is used for tires manufactured after 2000, the first two numbers are for the week, the other two are for the year.
As in the example is the 29th week of 2010.
3. Code UTQG - only tire quality
UTQG (The Uniform Tire Quality Grading) is a uniform tire quality classification system established by the US National Traffic Safety Agency NHTSA, based on 3 criteria:
- Treadwear (Treadwear 240) - wear resistance, is a comparison index written in three numbers, used to predict tire life. The compared object is a moderated standard tire, with a wear resistance of 100. The 240 number means that the upper tire has a wear resistance of 240% compared to the reference tire.
However, it should be clear that each company will have a unique standard, so Treadwear will only be used to compare tires in the same company.
- Traction (Traction A) : the grip of the tire, including 4 levels AA, A, B and C (AA is the highest). A tire, if rated at below C level, is not qualified to be used for transportation.
- Temperature (Temperature A) - the temperature of the tire, is the ability of the tire to withstand the heat produced at high speed as well as the ability to efficiently heat. Heat resistance levels range from A to C, directly affecting how well the tire can run at high speeds.
In the US, any tire sold must have a heat rating rated from C or above, ie at least 85mph.
You see, tires alone have a lot of interesting information that we don't know. It is said that knowledge is boundless, and only finding and cultivating us can make ourselves new.