Tire Size 275/70r18 vs 33×12.50r18
The main difference between 275/70r18 and 33×12.50r18 tire size lies in the section width. The 275/70r18 has a narrower width of 10.83 inches compared to 12.52 inches for the 33×12.50r18. This 15.6% width difference affects various performance aspects.
| / | R |
| / | R |
| Parameter | 235/35 R18 | 205/40 R18 | Differ. |
|---|---|---|---|
| Tire Height | |||
| Section Width | |||
| Circumference | |||
| Sidewall Height | |||
| Revolutions | |||
| Rim Size |
Fitment Guide
Replacing tires with significantly different sizes can require modifications to prevent rubbing or clearance issues. The 33×12.50r18 is only 0.4% larger in overall diameter than the 275/70r18.
So it should fit most vehicles designed for 275/70r18 tires without issues. Larger adaptations like lift kits would only be necessary if switching to a tire over 3% larger in diameter.
Ground Clearance
With a diameter of 33.02 inches, the 33×12.50r18 provides 0.13 inches more ground clearance than the 33.16 inch 275/70r18.
This slightly lower clearance could make the 275/70r18 more prone to scrapes over obstacles. However, the difference is minor, and both tires offer good clearance.
Gas Mileage
The wider 33×12.50r18 has a larger contact patch and more rotational mass, which leads to slightly higher rolling resistance.
This can reduce fuel efficiency compared to the narrower 275/70r18. However, real-world differences would be modest, given the small disparity in size.
Ride Comfort
The 33×12.50r18’s additional sidewall height cushions bump better than the 275/70r18. Its 7.51-inch sidewall dampens impacts versus 7.58-inch for the 275/70r18. This results in a slightly smoother ride over uneven pavement. But both absorb bumps well.
Aesthetics
The 33×12.50r18’s taller sidewall visually provides a subtly “stretched” look compared to the 275/70r18’s shorter sidewall. This taller profile better suits trucks and SUVs aesthetically. However, the difference is minor and subjective.
Handling & Stability
The 275/70r18’s shorter sidewall enables slightly quicker steering response and handling precision on the pavement.
But both sizes deliver responsive, stable handling for their intended use. Off-road, the 33×12.50r18’s additional traction aids stability.
Noise & Vibration
With a shorter, stiffer sidewall, the 275/70r18 transmits marginally more road noise and vibration to the cabin. The 33×12.50r18’s additional sidewall flex better dampens noise and vibration. However, the differences are minor – both tires are relatively quiet and smooth.
Durability & Wear
The narrower 275/70r18 may exhibit slightly more even treadwear across its width compared to the wider 33×12.50r18.
This could confer a modest advantage in tread life. However, both tires should deliver comparable durability and longevity for their intended purposes.
Adverse Conditions
Performance in rain, snow, and off-road is similar. The 33×12.50r18’s greater width provides a traction advantage, while the 275/70r18’s narrower footprint can cut through snow more effectively. Ultimately, both handle adverse conditions well.
Speedometer Difference
At an actual speed of 20 mph, the speedometer reads 0.4% lower with the 33×12.50r18 (19.92 mph) than the 275/70r18 (20 mph).
This minor difference has a negligible impact on real-world driving. Drivers can simply note that the 33×12.50r18 reads slightly lower.
What Does 33×12 50r18 Tire Mean?
The “33” in the 33×12 50r18 tire size means the tire has an overall diameter of 33 inches. The “12.50” means that the tire has a width of 12.50 inches. The “18” means that the tire has a rim diameter of 18 inches.
The “r” in 33×12 50r18 stands for “radial,” which is the most common type of tire. Now that we’ve gone over the basics of tire sizing, let’s compare the 275 70r18 and 33×12 50r18 tire sizes.
Our Observation
After comparing the 275/70R18 and 33×12.50R18 tire sizes, we found the differences to be relatively minor. Both offer capable performance for most drivers.
The 33×12.50R18 provides a bit more cushioned ride thanks to its additional sidewall height. Its wider tread also delivers slightly better traction, which could be advantageous in some off-road conditions.
However, the 275/70R18’s narrower tread contributes to fuel efficiency. And its shorter sidewall enables responsive handling on pavement.
Ultimately, either tire should satisfy most drivers. The slightly enhanced ride and traction of the 33×12.50R18 make it preferable for trucks and SUVs. But the 275/70R18 offers a great blend of attributes for all-around use.
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.
