What Do the Numbers Mean On a Tire?
- Vehicle Type. The letter that precedes the first string of numbers indicates the type of vehicle to match the tire.
- Width. Immediately following the capital letter or letters, you’ll see three digits that tell you a tire’s width in millimeters.
- Aspect Ratio. ...
- Construction. ...
- Rim Diameter. ...
- Load Index. ...
- Speed Rating. ...
What do the first three numbers on a tire mean?
Tire width/section width/cross section are the first three tire numbers of the code, in millimeters. The measurement shows the distance from the widest spot of the inner sidewall to the same of the outer sidewall. Tire width can vary depending on the rim, so tire engineers mount the items on specified rims while calculating.
How do you read the numbers on tires?
- The index is not a hard number; it's just a symbol of sorts. ...
- To find out how much your entire car can carry without putting undue strain on your tires, multiply the number you found in the Load-Carrying Capacity Per Tire chart by ...
- Never replace your tires with ones that have a lower load index than the original tires. ...
Which of the numbers and Letters on tires matter?
Your tire will also have a combination of letters and numbers called the DOT Code. The most important part of this combination is four digits that indicate when your tire was manufactured. For example, “2118” would mean that the tire was made during the 21 st week of 2018.
How to tell what numbers mean on ATV tires?
We’re going to simplify ride style to three main types:
- Work/chores
- Trail/dune riding
- Rocks/mud riding
What do the 3 numbers mean on tire size?
B: TIRE WIDTH The three-digit number following the letter is the tire's width (from side to side, looking at the tire head on) in millimeters. This may also be referred to as the section width. C: ASPECT RATIO The forward slash separates the tire width number from the two-digit aspect ratio.
What does the 265 70R17 mean?
An arrow points to the numbers 265/70R17 115T on the inner part of the tire sidewall. 265 is the width, 70 is the aspect ratio, R stands for radial, 17 is the wheel diameter and 115T is the load index and speed symbol. ©2022 Nitto Tire U.S.A. Inc.
What is the most important number on a tire?
Tire Diameter or Size: 215/65 R15 The very last number in the sequence, “15,” is the diameter of the tire. This is an important number—this is the number you'll refer to when you need to know your tire size! The “15” indicates that this particular tire would fit a rim with a 15-inch diameter.
What does the 275 on a tire mean?
The numbers in the tire size refer to its width, aspect ratio, and wheel diameter. "275/35R19" means the tire is 275 mm wide, has an aspect ratio (that is, the width divided by the height) of 35%, and fits on a 19" wheel.
What's the difference between 265 65 r17 and 265 70R17?
The 265/70R17 is a General Grabber ATX and the 265/65R17 is the stock Hankook. And just for fun, it doesn't look very big compared to a 26x4. 8” bike tire, it's just barely taller!
Which tire is wider 255 or 275?
The 255 tires have a similar rim width to the 275. Whilst the 275 tires are bigger the 255 tires are more suitable for the smaller cars. Since these are smaller tires, they will hold cars that are weighed over 800 kg. The 255 tires will not be as sturdy as the 275, but this also means the 255 tires will go faster.
Can I use 245 tires instead of 235?
The quick answer is yes you can replace 245/50-18 tyres with 235/50-18 but they will have 10mm (0.4 in) smaller overall diameter. Will only slightly effect speedo and odometer - ie speedo will read about 1.5% high.
Can I use 215 tires instead of 205?
Physically they should fit on the rim and tire without issue. The difference is going to be the rolling distance is a bit shorter for the new (to you) tires. 215 to 205 is 1cm difference in width.
Which tire is wider 70 or 75?
70 (or 75) is the ratio of the width to the sidewall height. So a 75 will be a taller tire, and closer to the height of the 6.70x15.
How much bigger is a 33 inch tire than a 275?
Tire size equivalent chart for 33", 35", 37" or 40" tires33" Tires (+/- 0.50" in overall diameter)275/65-2035X12.50-22325/45-24285/65-20325/50-22295/65-20315/60-2045 more rows
Are wider tires better?
From a safety point of view, both types have their good sides: On a dry road, wider tires will offer more grip than narrow ones, but the risk of aquaplaning will be higher with wide tires. – In the winter, narrow tires are better under extreme conditions as they provide higher surface pressure against the road.
What size is 285 60 r20?
285/60R20 tires are 33.5″ tall, have a section width of 11.2″, and fit wheels with a diameter of 20. The circumference is 105.1″ that translates into 603 revolutions per mile.
What is the DOT code for tires?
Department of Transportation (DOT) code must be on all tires to be legal for selling and usage in the US. These are the requirements of Federal law. The code is mostly for manufacturers, as it’s more convenient to recall tires using them. However, cautious drivers can also learn a lot from it.
What does the letter after the tire mean?
A letter after the respective word indicates the limit of temperature that the tire can safely dissipate. There are A, B, and C ratings, where A is the best, and C is relatively the worst. The A grade means the tire can withstand speeds over 115 mph. The B grade shows the tire withstands speeds between 100 and 115 mph.
What is the tire profile of 55?
So, 55 profile is 55% of the width, meaning the tire’s height is (taking the width of 205 mm) 112.75 mm or 4.4”. You may see tires without these tire numbers, meaning the tire’s profile is standard – 82%. Also, there are rarely tires with the ratio of three digits, which means it’s in millimeters.
What is LT tire?
LT – the tire is for light trucks (some SUVs, medium and heavy duty pickups of ¾-1 ton load capacities). ST – the tire is a special trailer tire used on utility, car, and boat trailers. T – the tire is temporary (spare). These are the tires that can be used until the repair or replacement of the main tire is done.
What does maximum inflation mean on a tire?
Maximum inflation shows how much cold pressure a tire needs, to hold the maximum load. Maximum load shows how much weight a cold tire with proper maximum inflation can carry. These tire numbers are not the recommended inflation and load.
What does speed rating mean on tires?
Speed rating shows the maximum speed at which your tire can dissipate heat. It’s usually one or two letters, or a letter and a number. If the tire speed capabilities exceed the maximum limit (Y – 186 mph), the load index and “Y” have to be in parenthesis.
How many digits are in a tire plant?
Plant code. Every legal tire plant in the world should have a two- or three-digit, two - or three -letter or a letter-number code . You can find these tire numbers and letters in the Tire Safety Group sorted list. This may be important for those who want to know whether the tire was made in the US.
What does 65 mean in a tire?
In this example, the aspect ratio number “65” means that the tire’s height is 65 percent of its width.
What is a D tire?
The other letter you might see here is a “D,” which denotes a tire that has a diagonalor bias plyconstruction.
What does 65 R15 mean?
The “R” in this sequence refers to the construction of this tire. Specifically, the “R” means that the layers run radially across the tire.
Where to find original equipment tire size?
You can see your original equipment tire size in your owner’s manual or on the placard generally located on the driver’s side door jam.
What does it mean when a tire has a higher speed rating?
A tire with a higher speed rating can handle heat better and provide more control at faster speeds. The maximum operating speed of a vehicle is no more than the lowest speed rating of all tires mounted on the vehicle.
What is a D tire?
D is for tires built with diagonal (crisscrossed) plies, called bias-constructed tires. They are also called conventional, x-ply, or cross-ply tires. Some motorcycle and trailer tires still use this internal construction. Some run-flat tires are identified with an F followed by the type of internal construction.
What does P class mean in truck tires?
P stands for passenger vehicle tire. P-class tires include cars, SUVs, crossovers, minivans and smaller pickup trucks. LT means light truck tire, designed for vehicles that are capable of carrying heavy loads, towing trailers, or for those looking for an extra heavy duty option.
What does ST mean on a truck?
These are often equipped on three-quarter or 1 ton trucks and SUVs. ST stands for Special Trailer. These tire sizes are meant for trailers, including fifth wheels and other travel trailers, as well as boat and utility trailers.
What are radial tires made of?
In a radial tire, the plies — layers of strong cords made of a blend of polyester, steel and fabric and coated with rubber — are laid perpendicular to the direction of travel.
What does P mean on a tire?
P identifies your tire as a Passenger Tire. The P stands for PMetric. If your tire size starts with LT rather than a P then it identifies the tire as a Light Truck tire.
What is the load limit on a passenger car tire?
On each U.S. passenger car tire, the load limit is listed in pounds. European tires have the load limit listed in kilograms and sometimes pounds. When it comes to Light Truck (LT) or Special Trailer (ST) tires, there are two load indexes branded (example - LT235/75R15 104/101S). In this example, the 104 corresponds to 1,984 pounds (see chart ...
What is LT tire?
LT tires are commonly used on trucks with dual rear wheels and are branded with two load indexes. The first number indicates load carrying capacity if the tire is installed on a truck with a single-wheel rear axle, and the second number applies when the tire is used in a dual rear application.
What does ST175/80R13 mean?
Tires beginning with a ST (for example ST175/80R13) indicate a Special Trailer tire and should only be used on car, boat or utility trailers. The load index and speed rating, or service description, are the numbers that follow the tire size.
What does the P mean on a tire?
P in this tire number stands for “P-Metric tire.” That means the tire is suitable for use on passenger vehicles–mainly cars and some crossovers. In place of this P, you might also see the letters “LT” (for light truck). If the first letter is missing, you’re dealing with a Euro-Metric tire. The most important thing to know about the first letter in the tire code is that each classification corresponds to a certain load capacity range. If you’re equipping tires on a vehicle, make sure that they can safely handle your vehicle’s curb weight and payload.
What is load index on tires?
Your load index is a more precise measurement of how much weight your tire can handle. A tire with a load index of “95” can handle up to 1521 pounds when properly inflated. Tires for passenger vehicles (see above: “P-Metric tires”) generally offer load indexes falling between 75 and 105, but other types of tires offer significantly higher capacities. What do the numbers on your tires mean? Any questions about load indexes can be directed to our service team. The “H” in this number represents your tire’s speed rating, i.e., how quickly you can travel without damaging the tire. A rating of H corresponds to a speed rating of 130 mph–much higher than any local speed limit. Spare tires, on the other hand, usually have lower speed ratings.
What is 215 tire number?
“215” is the width of the tire from sidewall to sidewall, given in millimeters. This section of the tire number is almost always three digits long. If your tires are too wide for your vehicle, you’re obviously going to run into trouble.
Tire Manufacturers
The largest font on the sidewall of a tire is usually reserved for advertising who made it. Mega brands like Goodyear, Michelin, and Yokohama make most of the tires for sale in the U.S. today.
Model Name
Tires have model names just like cars do. The model name will usually be listed after the manufacturer name, as in Michelin Pilot Sport or Yokohama Advan Apex.
How to Read Tire Size
A code on the sidewall explains many details about your tires. The code follows a pattern.
Treadwear, Traction, and Temperature
Typically in smaller font, often close to the tire’s inner edge, you’ll find a rating for treadwear, traction, and temperature grades.
Maximum Allowable Inflation
Usually located on the inner rim of the tire, in fairly small font, is the maximum inflation pressure. It is unsafe to inflate the tire beyond this point. However, it’s best not to use this as a guide when inflating your tires. Tires perform differently when carrying different weights, so your car’s weight affects the proper inflation level.
Maximum Load Rating
You will find the maximum amount of weight the tires can support also listed on the inner rim in small font. While you should never exceed this weight, it is only one factor in how much weight your vehicle can carry. A vehicle’s payload capacity is also affected by its suspension, its frame, and its own weight.
U.S. DOT ID Number
Each tire model gets assigned an identification number by the U.S. Department of Transportation. This is listed in small print on the inside rim of the tire. DOT Identification numbers are generally not something consumers need to know.
What does load index mean on a tire?
Load index is a code that indicates how many pounds a tire can carry at a given inflation level. In this instance, a load index of 92 would mean that tire is capable of carrying 1,389 pounds at 36 psi inflation. H — This indicates the speed rating. Speed rating is the highest speed a tire can safely handle, determined through lab testing.
What is a LT tire?
LT is for a light truck. ST is for a special trailer. T is for temporary, usually indicating a spare tire. European-standard tires won't have a prefix letter at all. 205 — This is the section width of the tread, from sidewall to sidewall. In this case, the tire's section width is 205 millimeters.
What is a 200 tread?
Treadwear grades were designed by the National Highway Safety Administration and take heat resistance, rolling resistance, and other factors into account, and a tire with a treadwear grade of 200 is rated with twice the tread life of one with a 100 grade.
What is the maximum speed of a tire?
Speed rating is the highest speed a tire can safely handle, determined through lab testing. In this case, an H-rated tire is good for speeds up to 130 mph. Code. Maximum Speed (mph) Q. 100.
Can you tell if a tire is a tire?
Your tires can tell you a lot — if you know how to read what they have to say. Many years ago, the tire industry established a set of standards for the information that's embossed on the sidewall of tires.
