315/70R17 in Inches: Dimensions, Performance, and Tire Size

Choosing the right tire size for your vehicle is essential for ensuring optimal performance, safety, and durability, especially when driving through tough terrains or during long highway trips. The 315/70R17 tire is a popular choice for off-road enthusiasts and truck owners who require superior traction and stability. 

With a tire width of 12.4 inches (315 mm) and an overall diameter of 34.4 inches (874 mm), the 315/70R17 offers a robust footprint that excels in providing comfort, durability, and traction. The 8.7-inch (221 mm) sidewall helps absorb impacts, protecting your vehicle and ensuring a smoother ride on uneven surfaces.

In this guide, we will explore everything you need to know about 315/70R17 tires, including their dimensions, key characteristics, performance across different terrains, and tips for choosing the right rim and vehicle compatibility. Stay informed about different tire sizes before making a purchase by exploring more guides on tire sizes in my blog.

What Do These Numbers 315/70R17 Mean?

The tire size 315/70R17 follows a standard nomenclature that can be broken down into specific details:

• 315: This number represents the width of the tire in millimeters, specifically 315 mm or 12.4 inches.
  
• 70: The aspect ratio is the height of the sidewall as a percentage of the width. In this case, the height is 70% of 315 mm, which equals 221 mm (8.7 inches).
  
• R: This letter indicates that the tire has a radial construction, which is the most common tire construction type, known for providing durability and even tread wear.
  
• 17: This number represents the diameter of the wheel that the tire fits, in inches. So, this tire is designed for a 17-inch rim.
  

Understanding the 315/70R17 in Inches and Metric

Here’s a quick breakdown of the specifications for the 315/70R17 tire:

Key Characteristics:

• Width: 12.4 inches (315 mm)
  
• Overall Diameter: 34.4 inches (874 mm)
  
• Sidewall Height: 8.7 inches (221 mm)
  
• Circumference: 108 inches (2744.4 mm)
  
• Wheel Size: 17 inches (431.8 mm)

How to Convert 315/70R17 to Inches?

Converting the 315/70R17 tire size from metric to inches is relatively simple:

• Width: 315 mm ÷ 25.4 = 12.4 inches (Width of the tire).
  
• Sidewall height: 12.4 inches × 0.70 = 8.7 inches (Sidewall height).
  
• Wheel diameter: 17 inches (Wheel diameter is already in inches).
  
• Overall diameter: 17 inches (Wheel diameter) + 2 × 8.7 inches (Sidewall height) = 34.4 inches (Overall diameter).

Tire Lifespan of 315/70R17: What You Need to Know

The lifespan of 315/70R17 tires typically ranges from 20,000 to 70,000 miles depending on tire type, usage, and maintenance.

• Mud-Terrain (M/T): 20,000 to 40,000 miles, best for off-roading but wears quickly on pavement.
  
• All-Terrain (A/T): 30,000 to 50,000 miles, a balanced option for both on-road and off-road use.
  
• Rugged-Terrain (R/T): 20,000 to 50,000 miles, combining features of both M/T and A/T.
  

Factors Influencing Lifespan:

• Driving Conditions: Highway driving extends lifespan; off-roading wears tires faster.
  
• Maintenance: Regular tire rotations, proper wheel alignment, and correct tire pressure can help maximize tire life.

Tire Construction: Why “R” Matters in 315/70R17

The “R” in the 315/70R17 tire size indicates that the tire uses radial construction. This is the most common construction method in modern tires. Radial tires are designed with layers of steel belts that run radially (from the center out) beneath the tread.

The radial design provides several advantages:

• Better Durability: Radial tires offer better heat resistance, which results in improved durability.
  
• More Even Wear: Radial tires wear evenly, which helps to extend their lifespan.
  
• Improved Performance: Radial tires provide better handling and fuel efficiency, making them a great choice for both on- and off-road vehicles.
  

315/70R17 Tire Circumference and Revolutions

The circumference of a 315/70R17 tire is 108 inches (2744.4 mm). This means that the tire travels 108 inches with each full rotation. Understanding the circumference is crucial for determining speed, tire wear, and performance.

• Revolutions per Mile: A 315/70R17 tire makes approximately 587 revolutions per mile.
  
• Revolutions per Kilometer: This tire makes about 364 revolutions per kilometer.
  

These measurements help in assessing the tire’s effect on speedometers, odometers, and fuel efficiency, as they directly influence the number of rotations the tire makes per unit of distance.

Tire Performance Across Various Terrains

The 315/70R17 tire excels in different terrains, providing excellent traction, stability, and durability. Its wider profile, tall sidewall, and rugged construction make it ideal for off-road and tough driving conditions. Here’s a breakdown of its performance across various terrains:

1. Off-Road Trails

The larger diameter and deep treads offer excellent traction on loose surfaces like gravel and dirt. The wide contact patch helps the tire stay afloat on soft ground, providing better control. This prevents the tire from sinking, making it perfect for off-road adventures.

2. Rocky and Uneven Terrain

The tall sidewall acts as a shock absorber, protecting the tire from impacts on rocky, uneven surfaces. Its width helps distribute weight more evenly, improving stability. This makes it ideal for navigating rough, rocky trails without damaging the tire.

3. Mud and Snow

The aggressive tread design digs into soft and slippery surfaces, ensuring excellent traction in mud and snow. The wide tire provides better flotation, preventing it from getting stuck. Its construction allows for greater clearance over deep mud or snow.

4. Sand

On sandy terrains, the wider footprint helps the tire “float” on top of the sand, reducing the risk of getting stuck. This feature enhances maneuverability in desert-like conditions. The tire’s design prevents it from sinking into loose, shifting sand.

5. On-Road Performance

While optimized for off-road use, the tire still offers smooth handling on highways. Its radial construction ensures a stable ride but may produce more road noise. Fuel efficiency might decrease slightly, but the trade-off is worth it for off-road capability.

Choosing the Right Rim for 315/70R17 Tires

Choosing the appropriate rim for your 315/70R17 tires is crucial to ensure optimal performance, safety, and longevity. This tire size is commonly used in off-road vehicles, trucks, and SUVs, and selecting the correct rim dimensions and specifications can significantly impact handling and ride quality.

• Recommended Rim Width: Ideal rim width for 315/70R17 tires is typically between 8.5 inches and 10 inches to ensure proper fitment and even tread wear.
  
• Rim Diameter: The tire is designed to fit a 17-inch diameter rim, which must match the tire’s specification for proper installation.
  
• Offset Considerations: For optimal performance, a wheel offset between 0 mm and +12 mm is recommended. This range helps prevent rubbing and ensures proper clearance.
  
• Backspacing and Clearance: Adequate backspacing ensures the tire doesn’t rub against suspension components or the wheel well. Refer to your vehicle’s specifications or consult a professional for the ideal backspacing.
  
• Aftermarket Wheel Options: When upgrading to aftermarket wheels, choose reputable brands like Method Race Wheels, AEV, and Fuel Off-Road that offer wheels designed for off-road conditions and larger tires like 315/70R17.
  

By selecting the correct rim dimensions and offset, you’ll enhance your vehicle’s performance and maintain safety and tire longevity.

315/70R17 vs Other Tire Sizes: What’s the Difference?

When choosing a tire, it’s important to compare 315/70R17 with other common tire sizes to understand differences in width, diameter, sidewall height, and performance. Below, we break down the comparison for popular tire sizes.

315/70R17 vs 275/70R17: Ground Clearance vs Fuel Economy

Which One to Choose?

• Choose 315/70R17 for better off-road traction and ground clearance.
  
• Choose 275/70R17 if fuel efficiency and a smoother ride on paved roads are priorities.
  

315/70R17 vs 305/70R17: More Traction vs Better Performance

Which One to Choose?

• Choose 315/70R17 if you need extra ground clearance and off-road performance.
  
• Choose 305/70R17 for a slightly more balanced tire with good performance on both highways and rough terrain.
  

315/70R17 vs 285/75R16: Larger Diameter vs Higher Sidewall

Which One to Choose?

• Choose 315/70R17 for more ground clearance and a larger diameter for off-roading.
  
• Choose 285/75R16 if you prefer better shock absorption and a smaller rim size.
  

By understanding the differences in tire sizes, you can select the right tire based on your specific driving needs and vehicle compatibility.

Vehicle Compatibility with 315/70R17 Tires

The 315/70R17 tire is well-suited for a range of light trucks, off-road vehicles, and SUVs that require durability and excellent traction. Its larger size and robust construction make it a popular choice for vehicles used in tough driving conditions, including off-roading and towing heavy loads. Here are some of the vehicles that commonly use the 315/70R17 tire size:

• Ford F-150
  
• Toyota Tundra
  
• Jeep Wrangler
  
• RAM 2500
  
• Ford Bronco
  

These vehicles benefit from the increased size and rugged performance that the 315/70R17 tire offers, making them ideal for those who enjoy off-road adventures or need extra towing capacity.

Alternate 315/70R17 Tire Sizes

If you’re looking for alternatives to the 315/70R17 tire, there are several sizes within 3% of the diameter that you can consider:

• 275/75R17: Diameter: 34.4″ (874 mm)
  
• 285/75R17: Diameter: 33.9″ (860 mm)
  
• 305/70R17: Diameter: 33.9″ (860 mm)
  

These alternatives provide options if you wish to upsize or replace your tires while maintaining similar performance and diameter for your vehicle. Ensure your vehicle stays safe and operates smoothly with our professional tire repair services, available right here.

FAQs

Q. What is the diameter of a 315/70R17 tire in inches? 

The overall diameter of a 315/70R17 tire is 34.4 inches, offering a large footprint for off-road stability and comfort.

Q. How long do 315/70R17 tires last? 

The lifespan of 315/70R17 tires can range from 20,000 to 70,000 miles depending on the terrain and maintenance.

Q. Can I use 315/70R17 tires on my truck? 

Yes, 315/70R17 tires are commonly used on trucks and SUVs, especially those designed for off-road or heavy-duty performance.

Q. What vehicles are compatible with 315/70R17 tires? 

Vehicles like the Ford F-150, Toyota Tundra, and Jeep Wrangler are commonly equipped with 315/70R17 tires for enhanced off-road capabilities.