What is the difference in the middle number on a tire?
The two-digit number after the slash mark in a tire size is the aspect ratio. For example, in a size P215/65 R15 tire, the 65 means that the height is equal to 65% of the tire’s width. The bigger the aspect ratio, the bigger the tire’s sidewall will be.
What does the middle two numbers on a tire mean?
The two-digit number following the slash in the tire size description is the tire’s aspect ratio. It is the sidewall height expressed as a percentage of the tire’s width. If the markings say 255/55R18, it means that the height of the sidewall is 255 multiplied by .
Can you change the middle number on tires?
Can I Change Tire Sizes? That said, the only dimensions you can change are the width and aspect ratio — never the wheel size, unless you buy replacement wheels — and you should always strive to keep the total height of the tire the same as the OEM.
Why are wider tires more expensive?
Wider tires tend to be more expensive because they are less common, and there is less competition between brands. Low profile tires are likely to sustain more damage to tires and wheel rims when encountering road debris and potholes. Larger and wider wheels decrease fuel efficiency and increase consumption.
What do the numbers mean on a tire size?
Understanding Three Numbers in Tire Sizes. The first number in a tire’s size, say 225, is the width of the tire in millimeters. This is pretty straight forward except that in the days of buying tires sized by the inch (remember 31/10.50×15), the first number was the height rather than the width.
What does a lower aspect ratio tire look like?
A lower aspect ratio means a lower-profile tire with a shorter sidewall, while a tire with a higher aspect ratio will have a taller sidewall and look more like a donut.
What are the different sizes of truck tires?
In addition to the inch rim sizes, there are also some unique tire sizes out there. Although not as common, tires are made in half-inch diameters for some heavy-duty light trucks, box vans, and heavy-duty trailers. These sizes are usually 14.5, 15.5, 16.5, 17.5, and 19.5 inches, and an example would be 33×12.5R16.5 118R.
What’s the difference between P Metric and Euro Metric tires?
Euro-Metric sizes are equivalent to P-Metric sizes in dimensions, but Euro-Metric sizes have subtle differences in their load-carrying ratings and capabilities. Euro-Metric tires are usually found on European cars, but they’re also used frequently used on SUVs and vans. Light Truck Metric tires sizes begin with the letters LT.
How do you calculate tire size?
You can use our tire size calculator to find the tire size, or you can use a few formulas. sidewall = section width × (60 ÷ 100) diameter = (sidewall × 2) + rim diameter. Thus, the wheel diameter is equal to the section width in inches times the aspect ratio divided by one hundred, times two, plus the rim diameter.
What is the second number on a tire?
The second number represents the width of the tire. In most cases with inch measurement tires the width will have a .50 decimal after the initial number. In example “A” this reads 12.50, meaning the tire width is 12 and 1/2 inches.
What is the most common tire size?
Here is the table of results sorted by wheel size then tire size. The two most common wheel sizes are 16×8 & 17×9. The two most common tire sizes are 265/75r16 & 285/70r17.
What size tires does my car need?
The minimum tire width 175 mm designates the safe tire width, 185mm and 195 mm are ideal tire widths and 205 mm is the maximum tire width. The maximum tire width is not ideal because the tire tread is wider than the inside rim bead.