Tire Size 285/70r17 vs 245/75r17

The main difference between 285/70R17 and 245/75R17 tire sizes is the tire’s Overall diameter. The 285/70r17 tire is 1.24 inches (31.5 mm) larger in diameter than the 245/75r17 tire.

This means the 285/70r17 tire will have a higher ground clearance and a larger contact patch, giving it better traction and handling in off-road conditions.

285/70r17 vs 245/75r17

This table compares tire sizes 285/70r17 and 245/75r17 for easier understanding of differences.

Fitment Guide

Replacement tires should be within 3% of the original tire’s overall diameter to avoid clearance issues or speedometer inaccuracies.

The overall diameter of the 285/70R17 is 3.8% larger than the 245/75R17. While the 285/70R17 may fit without modifications, larger tires like these may require a suspension lift or leveling kit to prevent rubbing at complete turn.

Ground Clearance

The 285/70R17, with a diameter of 32.71 inches, provides 1.24 inches more ground clearance than the 245/75R17 at 31.47 inches.

This added clearance is useful for off-road driving, helping prevent scrapes and damage from obstacles. However, the larger diameter also causes a lower speedometer reading for the 285/70R17 compared to the 245/75R17.

Gas Mileage

The 245/75R17, with its more minor contact patch and lower rotational mass, will likely provide slightly better fuel efficiency than the heavier 285/70R17.

This makes the 245/75R17 a good choice for daily driving and long trips where gas mileage is a priority.

Ride Comfort

While the 245/75R17 offers a smooth ride on pavement, the taller sidewall and greater air volume of the 285/70R17 absorb bumps better, resulting in superior comfort on uneven terrain.

This cushier ride reduces the harshness felt in the cabin when off-road.

Aesthetics

Visually, the difference between these sizes is subtle. The 285/70R17 has a slightly taller sidewall, giving it a “stretched” look compared to the 245/75R17.

This aesthetic suits trucks and SUVs well. However, the lower profile 245/75R17 contributes to a smoother, more aerodynamic appearance.

Handling & Stability

The 245/75R17 shorter sidewall enables sharper handling and quicker response on paved roads.

In contrast, the 285/70R17 extra sidewall flex reduces handling precision a bit but provides added stability and traction off-road or on uneven ground.

Noise & Vibration

With its shorter, stiffer sidewall, the 245/75R17 transmits more road noise and vibration into the cabin. The extra flex of the 285/70R17 sidewall dampens noise and vibration better for a more comfortable ride.

Durability & Wear

The potential for even treadwear and longer life is higher with the 245/75R17. The larger 285/70R17 can withstand more impacts, but its added weight could increase wear on suspension components.

Adverse Conditions

In snow and ice, the 245/75R17 narrower footprint can cut through to the pavement more easily.

But the 285/70R17 provides better traction in specific off-road conditions where a wider, grippier tread is advantageous. Both handle rain well.

Speedometer Reading

At an actual speed of 20 mph, the speedometer reads 20 mph with 285/70R17 tires equipped.

But with 245/75R17 tires, the speedometer reads 19.24 mph at the same actual 20 mph speed. This 0.76 mph speedometer difference should be considered.

What is the Main Difference Between 285/70R17 and 245/75R17?

The main difference between 285/70R17 and 245/75R17 tires is the overall diameter. The 245/75R17 tires are about 1.24 inches (31.5 mm) or 3.8% smaller in diameter compared to the 285/70R17 size.

Can I Use 245/75R17 Instead of 285/70R17?

While you could use 245/75R17 tires instead of 285/70R17, it’s not ideal. The 3.8% difference in diameter exceeds the recommended range of 3%, which can negatively impact vehicle performance and handling. Modifications may be necessary.

How Much Taller Is a 285/70R17 Tire Than a 245/75R17?

A 285/70R17 tire is approximately 1.24 inches (31.5 mm) taller than a 245/75R17 tire, which equates to the 245/75R17 tire being 3.8% smaller in overall diameter.

How Much Wider is a 285/70R17 Tire Than a 245/75R17?

A 285/70R17 tire is 1.57 inches (40 mm) wider than a 245/75R17 tire. This is a significant 14% difference in width.

Our Observation
The 285/70R17 and 245/75R17 sizes differ primarily in overall diameter, which impacts ground clearance, appearance, speedometer accuracy, and off-road capability.

For a blend of on-road comfort and off-road versatility, the moderately sized 285/70R17 is a good choice.

However, the 245/75R17 excels for responsive handling, efficiency, and pavement performance. Understanding these differences allows you to select the best tire for your needs.

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