Tire Size 275/55r20 vs 275/65r20
The main difference between 275/55r20 and 275/65r20 tires is the aspect ratio. The aspect ratio is the second number in the tire size designation, and it represents the height of the sidewall as a percentage of the tire’s width.
275/55r20 vs 275/65r20
This table of comparison will enable you to quickly understand the differences.
Fitment Guide
The overall diameter of 275/65r20 tires is 2.17 inches (55mm) larger than 275/55r20, a difference of 6.8%.
Replacement tires should be within 3% of the original size to prevent clearance issues or speedometer errors. The 275/65r20 may require adaptations like a lift kit to fit properly.
Ground Clearance
With a diameter of 34.07 inches, the 275/65r20 tire size provides 1.08 inches (27.5mm) more ground clearance than the 275/55r20 at 31.91 inches.
This added clearance aids off-road driving by preventing scrapes over obstacles. However, the larger diameter causes a lower speedometer reading.
Gas Mileage
The 275/55r20 smaller contact patch and lower rotational mass improve fuel efficiency, a big perk for daily drivers. The larger 275/65r20 may detract from mpg due to more rolling resistance and weight.
Ride Comfort
The extra sidewall height of the 275/65r20 absorbs road impacts better than the 275/55r20, providing a smoother ride over uneven terrain. The difference is modest but noticeable on very bumpy roads.
Aesthetics
Visually, the 275/65r20 will have a slightly taller sidewall, giving a subtly “stretched” look. Some vehicles suit this aesthetic over a low-profile appearance. The taller 70 aspect suits trucks and SUVs well.
Handling & Stability
The 275/55r20 shorter sidewall enhances handling precision and responsiveness on the pavement. The taller 275/65r20 sidewall flexes more, reducing handling sharpness slightly. Both deliver stable handling overall.
Noise & Vibration
The 275/55r20 transmits more road noise and vibration due to its stiffer sidewall. The 275/65r20 extra flex dampens noise and vibration somewhat. Differences are minor for a comfortable, quiet ride.
Durability & Wear
The 275/55r20 smaller size potentially exhibits more even wear and longer tread life. The larger 275/65r20 endures more impact, but its added weight causes more component wear.
Adverse Conditions
The 275/55r20 shorter sidewall makes it a bit more responsive in rain, snow, and off-road conditions. But the 275/65r20 extra clearance provides an advantage, and both handle adverse conditions well.
Speedometer Difference
At an actual speed of 20 mph, the speedometer reads 21.36 mph with 275/65r20 tires vs. 20 mph with 275/55r20. The larger diameter causes 275/65r20 speedometers to read 0.66 mph higher.
How Tall Is A 275/65r20 Tire?
The 275/65R20 tire has a height, also known as the overall diameter, of approximately 34.1 inches or 866 mm. The sidewall of the tire is about 7 inches or 178.8 mm. The tire is designed to fit a 20-inch wheel rim.
What Does Tire Size 275/55r20 Mean?
The tire size 275/55R20 provides specific information about the dimensions and construction of the tire. Here’s a breakdown of each part of the code:
- 275: This number represents the width of the tire in millimeters. In this case, the tire is 275 millimeters wide.
- 55: This number is the aspect ratio, which is the ratio of the tire’s height to its width. In this example, the height is 55% of the tire’s width.
- R: This letter indicates that the tire has a radial construction.
- 20: This number represents the diameter of the wheel (rim) in inches.
Our Observation
Based on the comparisons, the 275/65r20 offers a more cushioned ride and increased ground clearance, while the 275/55r20 provides sharper handling and superior fuel economy.
The choice comes down to ride comfort versus sporty responsiveness. Both tires deliver robust real-world performance regardless of aesthetic preference for taller or lower sidewalls. Carefully weigh your priorities to pick the best tire for your needs.

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.