275 70r18 vs 275 65r20 Tire Size
When it comes to off-road tires, you often hear about the different sizes of tires used. Most people know about the most common tire sizes, such as 235 55R19, 275 70r18 and 275 65r20. For those who don’t know what each of these numbers means, this article explains everything you need to know about choosing the right tire size for your vehicle.
275/70r18 vs 275/65r20 Table
275 70r18 | 275 65r20 |
Overall Diameter 33.16 inches | Overall Diameter 34.07 inches |
Width 10.83 inches | Width 10.83 inche |
Sidewall Height 7.58 inches | Sidewall Height 7.04 inches |
Radial Tire (A Radial-Ply Tire) | Radial Tire (A Radial-Ply Tire) |
Rim Size 18 inches | Rim Size 20 inches |
Circumference 104.17 inches | Circumference 107.05 inches |
Revs Per Mile 608 | Revs Per Mile 591 |
What Does 275 65r20 Tire Mean?
275 65r20 is the standard tire size. The first number, 275, is the width of the tire in millimeters. The second number, 65, is the sidewall height. This sidewall height is represented as a percentage of the width of the tire. In this case, it would be 65% of 275 mm, or 178.75 mm.
The final number, 20, is the diameter of the wheel that the tire will fit on. In this case, it would be 20 inches in diameter. Now that we know what all of the numbers mean let’s take a look at some of the pros and cons of each size.
Overall Diameter
One of the main differences between these two sizes is the overall diameter. The 275 70r18 size has an overall diameter of 33.16 inches. The 275 65r20 size has an overall diameter of 34.07 inches.
This may not seem like a big difference, but it can have an effect on the way your vehicle handles. A smaller diameter means that the tires will have a shorter contact patch with the ground. This can make the vehicle feel less stable, especially at high speeds.
Section Width
The section width of a tire is the width of the tire from sidewall to sidewall. The 275 70r18 size has a section width of 10.83 inches. The 275 65r20 size has a section width of 10.83 inches, as you can see that there is no difference between these two sizes.
This is important to know because a wider tire will have a larger contact patch with the ground. This can give you more traction, but it can also make the ride feel a little rougher.
Circumference
The circumference of a tire is the distance around the outside of the tire. The 275 70r18 size has a circumference of 104.17 inches. The 275 65r20 size has a circumference of 107.05 inches. The difference between them is 2.88 inches or about 2.7%.
If the circumference is too large, the speedometer will read lower than your actual speed. If the circumference is too small, the speedometer will read higher than your actual speed.
Revolutions Per Mile
The number of revolutions per mile (RPM) is how many times the tire will go around in one mile. The 275 70r18 size has an RPM of 608. The 275 65r20 size has an RPM of 591.
So, the 275 65r20 size will travel about 10 miles further with each revolution. This is important to know because it can affect your fuel economy. A tire with a higher RPM will travel further, but it will also use more fuel.
Sidewall Height
The sidewall height of a tire is the distance from the edge of the wheel to the top of the tread. The 275 70r18 size has a sidewall height of 7.58 inches. The 275 65r20 size has a sidewall height of 7.04 inches.
The 275 70r18 size has a taller sidewall. This can give the vehicle a little more cushioning and make the ride feel smoother. It can also make the vehicle feel more stable.
Wheel Size
The wheel size is the diameter of the wheel that the tire will fit on. The 275 70r18 size has a wheel size of 18 inches. The 275 65r20 size has a wheel size of 20 inches. The smaller wheel size will make the vehicle feel more responsive. It will also make the ride feel a little rougher. The larger wheel size will make the ride feel smoother.
Construction Type
The construction type of a tire is how the layers of the tire are put together. The 275 70r18 size has a construction type of radial. The 275 65r20 size has a construction type of radial.
Radial tires are the most common type of tire. They have layers that run perpendicular to the direction of travel. This gives the tire a more flexible sidewall. The result is a smoother ride and better fuel economy.
Our Observation
The main difference between 275 70r18 and 275 65r20 tire sizes is in the sidewall height. The 275 70r18 tire size is 0.54 inches or about 7.7% more than the 275 65r20 tire size. If you are looking for a tire with a taller sidewall, then 275 70r18 is the better option. If you are looking for a tire with a shorter sidewall, then 275 65r20 is the better option.
Conclusion
We hope this article helped us understand the differences between these two tire sizes. If you have any questions, please feel free to contact us. We would be happy to help you find the right tire for your vehicle. Thank you for reading! Have a great day! 🙂
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