Tire Size 275/70r18 vs 285/75r18
The main difference between 275/70R18 and 285/75R18 tires is their diameter. The 285/75R18 tires are 1.67 inches (42.5 mm) larger in diameter than the 275/70R18 tires.
This means the 285/75R18 tires will provide a slightly higher ground clearance and more off-road performance.
| / | R |
| / | R |
| Parameter | 235/35 R18 | 205/40 R18 | Differ. |
|---|---|---|---|
| Tire Height | |||
| Section Width | |||
| Circumference | |||
| Sidewall Height | |||
| Revolutions | |||
| Rim Size |
Fitment Guide
When replacing tires, the new set should be within 3% of the overall diameter of the original tires to avoid issues.
The 285/75R18 is 5% larger in diameter than the 275/70R18, so it may require modifications like a lift kit to fit correctly and prevent rubbing.
Ground Clearance
With a diameter of 34.83 inches, the 285/75R18 provides 1.67 inches more ground clearance than the 33.16 inch 275/70R18.
This added clearance is useful for off-roading by protecting against scrapes but causes a lower speedometer reading. The 275/70R18 reduced clearance increases road hazard risks.
Fuel Economy
The 285/75R18′ larger contact patch and heavier weight reduce fuel efficiency compared to the 275/70R18.
Less rotational mass and smaller contact patch confer better mileage, an important consideration for daily drivers.
Ride Comfort
The extra sidewall height of the 285/75R18 absorbs impacts better, providing a smoother ride off-road.
But on paved roads, the 275/70R18′ shorter sidewall actually delivers better comfort and responsiveness. The difference is small but noticeable on very uneven terrain.
Aesthetics
Visually, the difference between these sizes is subtle. The 285/75R18 taller sidewall has a slightly “stretched” look compared to the 275/70R18.
This aesthetic suits trucks and SUVs well, but the 275/70R18 maintains better aerodynamic efficiency.
Handling & Stability
The 275/70R18 shorter sidewall enables quicker steering response and handling precision on the pavement.
The 285/75R18 has more flex, reducing agility somewhat but providing stability off-road. Both deliver responsive, stable handling overall.
Noise & Vibration
The 275/70R18 stiff sidewall transmits more vibrations and road noise into the cabin.
The 285/75R18′ extra sidewall flex dampens noise and vibrations better for a more isolated ride. But differences are minor, with both providing comfort.
Durability
The 275/70R18 smaller size could allow for more even treadwear and a longer lifespan. The larger 285/75R18 endures more impact, but its added weight can increase drivetrain component wear over time.
Adverse Conditions
In snow or ice, the 275/70R18 narrower footprint can cut through to the pavement more effectively.
The wider 285/75R18 provides better heavy snow and muddy traction but could be more elegant. Both perform well overall in adverse conditions.
Speedometer Difference
When comparing speedometer readings for 275/70r18 and 285/75r18 tires, the 285/75r18 tires caused the speedometer to read 1.01 mph higher than the 275/70r18 tires at an actual speed of 20 mph.
This difference of 1.01 mph is due to the slightly larger diameter of the 285/75r18 tires. Overall, drivers should be aware that switching between these two tire sizes will cause a small change in speedometer reading.
What Does 275/70r18 Tire Mean?
This size is ideal for those who want to balance speed and traction. The “275” in 275 70r18 refers to the tire’s width in millimeters.
The “70” is the aspect ratio, which tells you how tall the sidewall is concerning the width. The “r” stands for radial, and the “18” is the diameter of the wheel in inches. The tire size 275/70r18 is equal to 33.2×10.8R18 in inches.
What Does 285/75r18 Tire Mean?
The tire size 285/75r18 is a radial tire designed to fit 18-inch diameter wheels. It has a width of 285mm, which is approximately 11.2 inches.
The tire’s aspect ratio is 75%, meaning the sidewall height is 75% of the tire’s width. The tire size 285/75r18 is equal to 34.8×11.2R18 in inches.
Can I Use 275/70r18 Instead of 285/75r18?
No, using 275/70r18 instead of 285/75r18 results in a 5% increase in diameter, exceeding the recommended 3% limit. It’s not advised as it may affect speedometer accuracy and handling.
How Much Taller Is A 285/75r18 Tire Than A 275/70r18?
The 285/75r18 tire is 1.67 inches (42.5 mm) taller than the 275/70r18 tire, representing a 5% increase in diameter.
The height of a 285/75R18 tire is 34.83 inches or 884.7mm, while a 275/70R18 tire has a height of 33.16 inches or 842.2mm.
How Much Wider Is A 285/75r18 Tire Than A 275/70r18?
The 285/75R18 tire is 0.39 inches (10 mm) wider than the 275/70R18 tire, which represents a 3.6% increase in width.
The width of a 285/75r18 tire is 11.22 inches or 285mm, while a 275/70r18 tire has a width of 10.83 inches or 275mm.
What Size Rim For 285/75R18?
The recommended rim size for a 285/75r18 tire is typically an 18-inch diameter rim. The ideal rim width for a 285/75r18 tire is typically in the range of 7.5 to 9.5 inches.
Therefore, a rim with an 18-inch diameter would be suitable for mounting a 285/75R18 tire.
275/70r18 vs 285/75r18
This comparison table will easily help you understand the differences between options.
What Size Rim For 275/70R18?
Typically, a 275/70R18 tire is best used with an 18-inch diameter rim. For optimal performance, the ideal rim width for this tire size ranges from 7 to 9 inches. Therefore, an 18-inch diameter rim would be suitable for mounting a 275/70R18 tire.
Our Observation
Based on the comparisons above, the 275/70R18 is likely the better everyday tire size for most drivers. It provides a smoother on-road ride, better fuel economy, and responsive handling at the cost of some off-road clearance.
The 285/75R18 is ideal for those who value added ground clearance for off-roading or a bold lifted stance. Its softer sidewalls absorb bumps well, but handling precision suffers.
We recommend the 275/70R18 as the best blend of comfort, efficiency, and performance for typical street usage. The 285/75R18 is best reserved for dedicated off-road vehicles.
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.
