Tire Size 285/70r17 vs 255/80r17
Changing tire sizes can significantly impact your vehicle’s performance and appearance. When considering a switch from 285/70r17 to 255/80r17 tires, it’s crucial to understand the effects on both on-road and off-road driving.
- Slightly increased overall diameter improves ground clearance
- Narrower width may enhance performance in mud and snow
- Taller sidewall can provide a smoother ride on rough roads
- Reduced width might decrease cornering grip on dry pavement
- Minor speedometer inaccuracy due to larger diameter
285/70r17 vs 255/80r17 Table
The primary difference between 285/70r17 and 255/80r17 tires lies in their width and aspect ratio. The 255/80r17 is narrower but has a taller sidewall, resulting in a slightly larger overall diameter.
Fitment Guide
The overall diameters of these tires are very close, with the 255/80r17 being just 1.1% larger. This small difference means both tires can be installed as replacements without issues.
According to industry guidelines, replacement tires should be within 3% of the original size to avoid clearance problems or speedometer errors. At just 1.1% difference, both the 285/70r17 and 255/80r17 will fit most vehicles designed for either size.
On-Road Impact
Switching from 285/70r17 to 255/80r17 tires can affect various aspects of your vehicle’s on-road performance. Let’s explore these impacts:
- Gas Mileage: The slightly larger diameter of the 255/80r17 tire may lead to a minor decrease in fuel efficiency due to increased rolling resistance. However, the difference is likely negligible in real-world driving conditions.
- Ride Comfort: The taller sidewall of the 255/80r17 tire can provide a smoother ride by absorbing more road imperfections. This can be particularly noticeable on rough or uneven surfaces.
- Speedometer Accuracy: The 1.1% increase in diameter will cause your speedometer to read slightly lower than your actual speed. For example, when your speedometer shows 20 mph, you’ll actually be traveling at 20.22 mph. While this difference is small, it’s worth noting for long trips or when driving near speed limits.
- Handling: The narrower width of the 255/80r17 tire may result in slightly reduced cornering grip on dry pavement. However, the taller sidewall can provide better stability during straight-line driving.
- Aesthetics: The narrower profile of the 255/80r17 tire may give your vehicle a more streamlined appearance, which some drivers prefer.
Off-Road Impact
For off-road enthusiasts, the switch to 255/80r17 tires can bring some notable changes to your vehicle’s capabilities:
- Ground Clearance: The 0.35-inch increase in diameter translates to a marginal gain in ground clearance. While this difference is small, it can be beneficial when navigating obstacles or rough terrain.
- Traction: The narrower width of the 255/80r17 tire can provide better performance in mud and snow by “cutting” through these surfaces more effectively. However, it may offer slightly less traction on loose gravel or sand compared to the wider 285/70r17.
- Flotation: The reduced width may result in less “flotation” on soft surfaces like sand or deep mud. This could potentially increase the risk of getting stuck in extremely challenging conditions.
- Durability: The taller sidewall of the 255/80r17 tire may offer improved protection against rock damage and punctures when off-roading, potentially increasing tire longevity in rough conditions.
What is the Difference Between 285/70r17 and 255/80r17?
The main difference between 285/70r17 and 255/80r17 tires is their width and aspect ratio. The 285/70r17 is wider but has a lower profile, while the 255/80r17 is narrower with a taller sidewall.
This change in dimensions affects various aspects of the tire’s performance, including handling, ride comfort, and off-road capabilities.
Can I Use 255/80r17 Instead of 285/70r17?
Yes, you can use 255/80r17 instead of 285/70r17. The overall diameter difference between these two tire sizes is 0.35 inches or 1.1%, which falls within the recommended 3% difference limit.
This makes the interchange generally suitable for most vehicles without significantly affecting performance or safety.
How Much Taller Is a 255/80r17 Tire Than a 285/70r17?
A 255/80r17 tire is 0.35 inches (9 mm) taller than a 285/70r17 tire. The 285/70r17 has a diameter of 32.71 inches (830.8 mm), while the 255/80r17 has a diameter of 33.06 inches (839.8 mm), resulting in a 1.1% increase in overall height.
How Much Wider is a 285/70r17 Tire Than a 255/80r17?
A 285/70r17 tire is 1.18 inches (30 mm) wider than a 255/80r17 tire. The 285/70r17 has a width of 11.22 inches (285 mm), while the 255/80r17 has a width of 10.04 inches (255 mm), representing a 10.5% difference in width.
Our Observation
Switching from 285/70r17 to 255/80r17 tires offers a mix of benefits and trade-offs. The narrower, taller profile can improve ride comfort and off-road performance in certain conditions, particularly in mud and snow.
However, it may slightly reduce on-road cornering grip and flotation in deep sand. The minimal impact on speedometer accuracy and fuel efficiency makes this change relatively seamless for most drivers.
Ultimately, the decision depends on your driving preferences and the terrain you frequently encounter. For those seeking a balance between on-road comfort and off-road capability, the 255/80r17 tire size can be an attractive option.
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.