What Does 285 Mean on a Tire?
The number 285 on a tire refers to the width of the tire in millimeters from sidewall to sidewall when measured on a properly mounted rim.
In other words, it means your tire is 285 millimeters wide. This number is part of a tire’s size information, which is usually displayed on the sidewall.
Understanding Tire Size
When you look at the full size information on a tire, you’ll see a string of numbers and letters that looks something like this: 285/75R16. Here’s what each part means:
- 285 is the width of the tire in millimeters measured from sidewall to sidewall
- 75 is the aspect ratio, which is the height of the sidewall expressed as a percentage of the width (in this case, the sidewall height is 75% of 285mm)
- R stands for “radial”, which is the most common tire construction type today
- 16 is the diameter of the wheel rim in inches
So in this example, the tire is 285 millimeters wide, the sidewall height is 75% of that width, it has a radial construction, and it fits on a 16-inch diameter wheel.
Why Tire Width Matters
The width of a tire, like our 285 example, impacts several key characteristics of vehicle performance:
- Traction: Wider tires put more rubber on the road, which can provide better traction and handling, especially in dry conditions. However, extremely wide tires can actually reduce traction in wet or snowy conditions.
- Ride comfort: Wider tires have a larger contact patch with the road, which can result in a smoother, more comfortable ride. The sidewalls are usually shorter too, reducing tire flex.
- Appearance: On many vehicles, especially sporty ones, wide tires can provide a more aggressive, muscular appearance that many people find appealing.
- Fuel economy: All else being equal, wider tires tend to slightly reduce fuel economy compared to narrower ones due to increased rolling resistance.
Choosing the Right Width
When selecting tires, it’s important to choose a width (and other dimensions) that are appropriate for your specific vehicle make and model. Consult your owner’s manual, tire information placard, or a professional tire supplier to determine the proper size.
Going too wide or too narrow can negatively impact handling, ride quality, and even safety in some cases. A 285 width tire, for instance, would be excessively wide for a compact car but might be just right for a large truck or SUV.
Conclusion
In summary, the number 285 on a tire refers to the tire’s width in millimeters. Tire width is an important factor in your vehicle’s performance, with wider tires offering better dry traction and handling while narrower tires are more fuel-efficient and perform better in wet and snowy conditions.
When choosing a tire width, consider your vehicle, driving conditions, and performance needs. Always ensure any new tire size is compatible with your vehicle. If you’re unsure, consult a tire professional for guidance.
Understanding what the numbers on your tire mean empowers you to make informed decisions about your tires and your vehicle’s performance. With the right tires, you can enjoy a safer, more comfortable driving experience in any condition.
Meet Caitlin McCormack, a Tire Size Expert and Blogger Passionate About Everything Related to Tires. With Years of Experience in the Tire Industry, Caitlin Has Become an Expert in Tire Sizes and Their Impact on Vehicle Performance.