Tires are one of the car consumables that we buy most often. Sometimes you may hear the question: “what does BSW mean on tires?” Meanwhile, some people have gained so much expertise that they can buy tires with their eyes closed. Similarly, others experience problems when facing a wide range of options. Numbers, letters, codes, abbreviations – sometimes it seems that tire manufacturers have invented all that just to confuse us. But the truth is, all those specifications are needed to help us make the right choice. Once you figure out how to read tire codes, you will realize how much easier tire shopping will become. In this article, we are going to mention the most widely used markings and codes. Among all other things, you will learn what BSW abbreviation means and why it is important.
Tire specifications chart
|Metric||Meaning||Abbreviation / Code||Example|
|Tire width||Distance from one sidewall to another (millimeters)||Three digits||P225/50R16|
|Aspect Ratio||Sidewall height to tire width ratio (mm)||Two digits||P225/50R16|
|Tire construction||Indicates the way cord plies are arranged in a tire||R- radial, D- diagonal, or B - bias-belted||P225/50R16|
|Wheel diameter||Diameter of a wheel rim (inches)||Two digits||P225/50R16|
|Load index||An index that represents the maximum weight (in kilos) that a tire can bear||Three digits||106H|
|Speed rating||Represents the maximum speed at the maximum load||Letters: Q, R, S, T, H, V, VR, W, Y, ZR||106W|
|Application||Defines the specifics of tire application||P - passenger, LT - light truck||P225/50R16|
This is not a comprehensive chart. In reality, a tire sidewall contains much more information. It is just impossible to discuss all of it in one short article. Other important specifications that always appear on tires are:
- Brand name;
- Country of origin;
- Type of pattern;
- Manufacturing date code, etc.
In the USA this information is usually confined in a DOT code. DOT stands for the US Department of Transportation. Letters and digits that follow this abbreviation encode basic manufacturer’s information. Most of it is usually disregarded by consumers, but the last four digits are definitely worth paying attention to. They indicate the time when the tire was manufactured. Since the tire age directly affects vehicle safety, it is always important to know it. Besides, manufacturers occasionally have to call back a batch of tires due to safety issues or defects. Therefore, it is important that you know where your tires come from so that you can react to such callbacks.
How to Calculate Tire Size?
Tire size calculators are available online in abundance. They can help you define some important metrics of the tire based on tire width, aspect ratio, and wheel diameter. Such calculators also allow you to compare different tire sizes to see which is perfect for your vehicle.
What wheel size should I choose?
One of the most popular questions that car owners ask is: “How does wheel size affect speed?” Many drivers feel tempted to get larger wheels to improve the aesthetics of their vehicles and achieve a more aggressive and sporty look. However, sometimes it is not the best decision.
The thing is, increasing wheel size results in a decrease of driving force, which in its turn, leads to a decrease in acceleration.
This is how alterations in wheel size affect speed. Large diameter truck mud tires are great when you need better traction and control over your vehicle in difficult road and off-road conditions. However, if you care about acceleration and fuel efficiency, you should go for smaller-diameter tires. Ideally, you should not deviate much from the wheel size designed by the manufacturer of your vehicle.
Additional Information Found on Tire Sidewall
More-or-less experienced car owners are familiar with the above-mentioned tire codes and metrics. But what about others, less known and less important. But still rather interesting facts? Few people can answer straight away what BSW abbreviation stands for. If you are curious about that, keep reading, we are about to decipher more tire codes!
What does SL mean on a Tire?
SL stands for standard load. This is a load capacity class typical for P-metric tires. Standard load indicates that the maximal load capacity of a tire is achieved at the load pressure of 35 psi. Other possible load ranges are XL – extra load and LL – light load. This marking is only valid for P-metric tires LT-metric tires (including mud tires for truck) have different letter codes.
It is very important to choose tires that fit your vehicle load. When replacing a tire you should always make sure that the load capacity of a new tire is the same or greater than load capacity of an existing one.
What does SL BSW mean on a tire?
We have already figured out how to decipher the SL abbreviation. Now is the turn of BSW. These three letters stand for black sidewall. This means that the sidewall of a tire is completely black:
- pure black letters;
- absolutely black numbers.
All the tire information is embossed on a sidewall in such a way that it appears plain black from a distance. Many car owners prefer such design, since it creates a uniform look. White letters are distracting and less stylish-looking.
On the other hand, black writings on black surface may be rather hard to read, especially after the tires have been in use for some time. Manufacturers are constantly inventing ways to make sidewall coding more distinguishable, while maintaining the stylish, uniform look.
The importance of such marking might be questionable, but only for those who you buy tires in physical stores. People who order tires online rely solely on codes to choose the right characteristics. Sometimes images on a website do not convey the real picture, while sidewall coding is something that can give you the most comprehensive information.
Now that you know how to read tire sidewall information, you can get better prepared for your next visit to a tire store. There is still so much other aspects to learn, but these are the basics that can help you navigate your way to your perfect tires.