Tire Size 285/70r17 vs 255/75r17
The main difference between 285/70r17 and 255/75r17 tires is that the 285/70r17 tires are 1.18 inches (30 mm) larger in section width than the 255/75r17 tires.
285/70r17 vs 255/75r17
This comparison table will provide you with a quick and easy way to comprehend the distinctions.
Fitment Guide
With a 2% larger overall diameter, 285/70R17 tires remain within the 3% limit for directly replacing 255/75R17 tires. No modifications are needed, but the slightly larger size will cause a minor speedometer inaccuracy.
Ground Clearance
The 2% larger diameter of the 285/70R17 adds 0.65 inches (16.5mm) of ground clearance over the 255/75R17.
This modest increase can help with light off-roading and clearing obstacles. However, the difference is slight, and both provide sufficient clearance for most conditions.
Gas Mileage
The 285/70R17 is slightly less fuel efficient due to its 2% larger diameter and 11.8% wider tread.
The increased rolling resistance and rotational mass hinder efficiency. For longer highway drives, the 255/75R17 is the better choice for gas mileage.
Ride Comfort
With just a 4.3% taller sidewall, the 285/70R17 absorbs impacts slightly better, leading to a modest improvement in ride quality over uneven roads. But both sizes offer very compliant, comfortable rides.
Aesthetics
Visually, the 285/70R17 has a tougher, more rugged look thanks to the wider tread and slightly taller sidewall.
This aesthetic is often preferred for trucks and SUVs over the more car-like 255/75R17 appearance.
Handling & Stability
The 285/70R17’s wider tread provides more grip and stability during cornering and evasive maneuvers.
But the taller sidewall is slightly less responsive. Both offer solid handling, but the 255/75R17 has a handling advantage on pavement.
Noise & Vibration
With its larger air cavity and more flexible sidewall, the 285/70R17 is marginally better at absorbing noise and vibrations. But both transmit minimal noise and are very refined.
Durability & Wear
The 285’s wider tread means it wears slightly faster in the middle of the tread. And the larger tire puts more stress on suspension components. Even wear life is nearly identical for both sizes.
Adverse Conditions
Performance in rain, snow, and light off-roading is comparable. The 255/75R17 is slightly better in deep snow, while the 285/70R17 has a bit more capability over rough terrain. Overall traction is excellent with both.
Speedometer Reading
Due to its 2% larger diameter, the 285/70R17 causes the speedometer to read 0.41 mph higher than the actual speed. At 20 mph, the speedometer shows 20.41 mph. The 255/75R17 matches the speedometer precisely.
What Does The 70 Mean On 285 70r17?
The “70” in 285/70R17 refers to the aspect ratio of the tire, which is the height of the sidewall as a percentage of the tire’s width. In this case, the sidewall height is 70% of the width of the tire.
How Much Bigger Is A 285 Tire Than A 255?
The 285 tire is approximately 30 millimeters wider than a 255 tire. This difference in width can affect the tire’s grip, handling, and fuel economy. The exact size difference in inches will depend on the specific tire models being compared.
Our Observation
After reviewing the differences, we observed that the 285/70R17 is the best choice for trucks, SUVs, and off-road use due to its added ground clearance, stability, and rugged aesthetics.
However, the 255/75R17 is likely the better option for passenger cars and on-road driving because of its responsive handling, even treadwear, and improved fuel efficiency.
The 255/75R17 is the recommended tire size for most drivers because of its well-rounded on-road performance and long tread life. But the 285/70R17 is ideal for truck and SUV owners who regularly go off-road or require maximum ground clearance.
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.
