Tire Size 275/55r20 vs 33×12.50r20
The main difference between 275/55R20 and 33×12.50R20 tires lies in their overall diameter. The 33×12.50R20 tire size is 1.11 inches larger than the 275/55R20 tire size. This means that the 33×12.50R20 tire is taller than the 275/55R20 tire, providing greater ground clearance.
Fitment Guide
When replacing tires, it is generally recommended to get new tires within 3% of the diameter of the original tires. This helps ensure proper fitment and prevent clearance issues.
The 33×12.50r20 tires exceed this 3% threshold, with a 3.5% larger diameter than the 275/55r20 tires.
Switching to the 33×12.50r20 tires may require modifications like a suspension lift or leveling kit to accommodate the larger size. Rubbing or interference issues could occur without proper modifications, especially at full steering lock.
Ground Clearance
The increased diameter of 33×12.50r20 tires provides 1.11 inches more ground clearance than 275/55r20 tires. This extra clearance is beneficial for off-roading over obstacles, rugged terrain, or when navigating inclines. The downside is that larger tires can reduce speedometer accuracy.
In contrast, the smaller 275/55r20 diameter lowers the vehicle height and reduces ground clearance. This makes scraping or bottoming out more likely when driving over obstacles, bumps, or uneven terrain. However, it provides better speedometer accuracy.
Gas Mileage
The 33×12.50r20 tires are larger in both diameter and width compared to 275/55r20 tires. The increased size adds more rolling resistance and rotational mass, reducing gas mileage.
So, drivers prioritizing fuel efficiency may want to opt for the smaller 275/55r20 tire size.
Ride Comfort
Larger diameter tires like the 33×12.50r20 provide more sidewall height and flex, allowing them to better absorb impacts from uneven roads and bumps. This cushier sidewall delivers a more comfortable ride, especially over rough terrain.
The shorter sidewalls of 275/55r20 tires do not dampen impacts as effectively. These tires tend to transmit more vibration and harshness from the road into the cabin. However, some drivers may prefer the more responsive, sportier feel.
Aesthetics
Aesthetically, the choice comes down to personal preference. Some may prefer how the larger 33×12.50r20 tires fill out the wheel wells, delivering a rugged, aggressive look.
Others may opt for the more streamlined appearance of lower-profile 275/55r20 tires.
Handling & Stability
The 275/55r20 tires offer sharper handling and quicker steering response thanks to the shorter, stiffer sidewalls. In contrast, the larger 33×12.50r20 tires exhibit more sidewall flex, reducing handling precision slightly.
However, the 33×12.50r20 tires provide stability advantages, especially for off-road driving, where the larger footprint delivers enhanced traction. Both tires deliver good overall handling and stability.
Noise & Vibration
Tires with a shorter sidewall, like the 275/55r20, tend to transmit more noise and vibration into the cabin. The extra cushioning from the taller sidewalls of 33×12.50r20 tires helps dampen noise and vibrations.
Durability & Wear
The 275/55r20 tires may exhibit slightly more even treadwear and longer lifespan thanks to the shorter sidewall and optimal fitment for most vehicles.
The added weight and impacts endured by 33×12.50r20 tires can accelerate wear on the tires and vehicle components.
Adverse Conditions
The narrower 275/55r20 tires can cut through to the road surface more effectively, enhancing winter traction for snow and ice driving.
Meanwhile, the wider 33×12.50r20 tires provide an advantage in deep mud or rugged off-road conditions. Both handle adverse conditions relatively well.
Speedometer Reading
Due to the 3.5% larger diameter, the speedometer reads 0.70 mph higher with 33×12.50r20 tires compared to 275/55r20 tires at an actual speed of 20 mph.
Drivers should account for this discrepancy in speedometer accuracy when switching tire sizes.
What Is 275/55r20 in Inches?
The 275/55R20 tire size converts to 31.9×10.8R20 in the high flotation sizing system, which uses inches for width and diameter measurements.
Specifically, 275/55R20 tires have an overall diameter of 31.9 inches (or 810.6 mm). The tread width measures 10.8 inches (or 275 mm). And this tire fits wheels with a 20-inch diameter (or 508 mm).
What Is 33×12.50r20 in Metric?
Considering standard metric tire sizes, the closest match to 33×12.50R20 is 325/50R20, with a width of 325mm and an aspect ratio of 50.
This metric size approximately corresponds to the 33-inch diameter and 12.5-inch width.
Is 275/55r20 A 33 Tire?
No, 275/55r20 is not a 33 tire. As per our calculation, the 275/55r20 tires are 1.11 inches (28.22 mm) smaller in diameter than the 33×12.50R20 tires.
The diameter of a 33-inch tire is 33 inches, while the diameter of a 275/55r20 tire is 31.91 inches.
Will 33×12.50R20 Fit 275/55r20?
No, fitting 33×12.50R20 tires on a vehicle originally equipped with 275/55r20 tires is not advised.
The difference in diameter between the two tire sizes is 3.5%, exceeding the recommended limit of 3%. This can affect the speedometer accuracy and may lead to other handling issues.
How Much Wider Is A 33×12.50R20 Tire Than A 275/55r20?
The 33×12.50R20 tire is 1.69 inches (43 mm) wider than the 275/55r20 tire. The tire size 33×12.50R20 is 12.52 inches (318mm), while 275/55r20 is approximately 10.83 inches(275mm).
This is a 15.6% increase in width when going from the narrower 275 tire to the substantially wider 33-inch tire despite having the same 20-inch wheel diameter.
How Much Taller Is A 33×12.50R20 Tire Than A 275/55r20?
Even though both tires have the same 20-inch wheel diameter, the 33×12.50R20 tire is taller than the 275/55R20 tire by 1.11 inches.
The 33×12.50R20 tire has a height of around 33.02 inches (838.72mm), while the 275/55R20 tire is approximately 31.91 inches (810.5mm).
This increase of 28.22mm represents a 3.5% gain in overall diameter when switching from the 275/55R20 tire to the taller 33-inch tire.
What Size Rim Fits A 33×12.50r20?
Generally, 33×12.50R20 tires can be mounted on wheels with a diameter of 20 inches and a width range of 8.5-11 inches. Consult your vehicle’s owner’s manual or a tire professional for the appropriate size and wheel fitment.
What Size Rim Fits A 275/55r20?
If you plan to mount 275/55r20 tires on 20-inch diameter wheels, remember that the recommended rim width for such tires falls between 7.5 inches and 9.5 inches.
Our Observation
Based on the differences between 275/55r20 and 33×12.50r20 tires, the 275/55r20 size seems optimal for most on-road driving.
The lower profile provides sharper handling, a smoother ride on pavement, improved fuel efficiency, and better long-term durability.
Meanwhile, the 33×12.50r20 tires are better suited to off-road adventures thanks to the larger diameter, increased ground clearance, and enhanced traction over rough terrain.
For a versatile tire that balances on and off-road performance, we favor the 275/55r20 as the best overall choice for most drivers and conditions. The differences are minor, but the lower profile 275/55r20 tire offers the best blend of key features.
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.