Tire Size 315/70r17 vs 285/70r17
Ever wondered about swapping your beefy 315/70R17 tires for a slightly slimmer 285/70R17? Buckle up as we dive into the nitty-gritty of this tire transition and explore how it might impact your ride both on and off the road.
- Narrower width could enhance steering response
- Smaller tires might offer a smoother ride on paved roads
- Decreased ground clearance may limit off-road capabilities
- Potentially better traction in mud and sand conditions
315/70r17 vs 285/70r17
Fitment Guide
In this case, 285/70R17 tires are 4.8% smaller in diameter than 315/70R17 tires, exceeding the recommended 3% difference.
This means switching to the smaller size is not recommended without making necessary adjustments to your vehicle to prevent rubbing or clearance issues.
On-Road Impact
Switching to a smaller tire size like 285/70R17 from 315/70R17 will affect your vehicle’s performance on paved roads. Here’s what you might notice:
- Speedometer Accuracy: Your speedometer will read about 5.1% faster than your actual speed due to the smaller tire circumference. At 20 mph, your actual speed would be closer to 19 mph.
- Ride Comfort: The smaller sidewall height of 285/70R17 tires may result in a slightly firmer ride compared to the taller 315/70R17 tires. However, this difference may be minimal and depends on the specific tire model and construction.
- Fuel Economy: With the smaller 285/70R17 tires, your engine will have to work slightly harder to maintain the same speed due to the increased revolutions per mile. This could lead to a minor reduction in fuel efficiency.
Off-Road Impact
If you take your vehicle off-road, here are some potential effects of switching to 285/70R17 tires:
- Ground Clearance: The smaller overall diameter of 285/70R17 tires will reduce your vehicle’s ground clearance by about 0.83 inches (21 mm). This might slightly limit your ability to clear obstacles on the trail.
- Traction: The narrower tread width of 285/70R17 tires could provide less flotation and traction in soft terrain like sand or mud compared to the wider 315/70R17 tires. However, the actual impact will depend on the specific tread design and compound of the tires you choose.
- Aesthetics: Going from 315/70R17 to 285/70R17 tires will give your vehicle a slightly less aggressive and narrower stance. The visual difference may be noticeable to discerning eyes.
What is the Main Difference Between 315/70r17 and 285/70r17 Tires?
The primary difference is in the overall diameter, with 315/70R17 tires being approximately 1.65 inches (42 mm) taller than 285/70R17 tires. The width also differs, as 315/70R17 tires are 1.18 inches (30 mm) wider.
Can I Use 285/70r17 Tires Instead of 315/70r17?
It’s not recommended to switch from 315/70R17 to 285/70R17 tires without making necessary adjustments to your vehicle.
The 4.8% difference in overall diameter exceeds the recommended 3% limit and could cause rubbing or clearance issues.
How Much Taller is a 315/70r17 Tire Than a 285/70r17?
A 315/70R17 tire is approximately 1.65 inches (42 mm) taller than a 285/70R17 tire. This height difference comes from the larger sidewall height and overall diameter of the 315/70R17 size.
How Much Wider is a 315/70r17 Tire Than a 285/70r17?
A 315/70R17 tire is 1.18 inches (30 mm) wider than a 285/70R17 tire. This width difference can affect the tire’s contact patch, traction, and overall appearance on your vehicle.
Our Observation
Switching from 315/70R17 to 285/70R17 tires brings both benefits and drawbacks. On-road, you might enjoy improved fuel efficiency and a smoother ride, but at the cost of slightly reduced grip and speedometer accuracy.
Off-road, the narrower tires could perform better in some conditions but may struggle with ground clearance and rock crawling.
The 4.8% difference in diameter, while exceeding the recommended 3% limit, may not drastically impact daily driving for most users.
However, for serious off-roading or performance applications, this difference could be significant and may require additional vehicle modifications.
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.