305/70R18 Tire Guide: Specs, Comparisons, and Top Picks

The 305/70R18 tire size measures 34.8 inches (885 mm) in overall diameter, 12 inches (305 mm) in width, and fits an 18-inch (457 mm) wheel. It has a sidewall height of 8.4 inches (214 mm), a circumference of 109.3 inches (2779 mm), and completes about 580 revolutions per mile (360 per km).

This size is widely used on trucks, SUVs, and off-road vehicles, offering excellent ground clearance, strong traction, and added stability. Drivers choose the 305/70R18 for its balance of off-road durability and on-road comfort, making it a reliable option for both adventure and daily driving.

For more detailed information about tire sizes, you can explore our article on tire sizes.

Key Specifications of the 305/70R18 Tire Size

The 305/70R18 tire size is designed for larger vehicles like trucks and SUVs, offering a balance of off-road durability and on-road comfort. Below are the key specifications of this tire for better understanding:

These dimensions ensure that the tire can handle both off-road challenges and provide stability on highways, making it an ideal option for trucks and SUVs used in various conditions.

Understanding the 305/70R18 Tire Size

The 305/70R18 tire size is composed of several elements that determine its performance, fit, and compatibility with different vehicles.

• 305: The tire’s width is 305 millimeters, or about 12 inches. This is the measurement across the tire’s tread and plays a key role in determining traction and stability.
  
• 70: The aspect ratio of the tire, which is 70% of the tire’s width. This indicates the height of the sidewall, which affects ride comfort and handling.
  
• R: The tire features radial construction, the most common type of tire design, which enhances strength and durability.
  
• 18: The diameter of the wheel in inches, meaning the tire is designed to fit an 18-inch wheel.
  

This configuration is ideal for vehicles like SUVs, trucks, and off-road vehicles that need additional support and better traction.

How to Convert 305/70R18 to Inches?

To understand the dimensions of a 305/70R18 tire in inches, follow these simple steps:

1. Width: Convert 305 mm to inches by dividing by 25.4:
   
   • 305 ÷ 25.4 = 12 inches
     
   • This gives you the total tread width of the tire.
     
2. Sidewall Height: Multiply the width by 0.70 (70% of the width):
   
   • 12 × 0.70 = 8.4 inches
     
   • This is the height of one sidewall from the rim to the outer tread.
     
3. Overall Diameter: Add the sidewall height (top and bottom) to the wheel diameter (18 inches):
   
   • 8.4 × 2 + 18 = 34.8 inches
     
   • This is the full height of the tire from ground to top tread.
     
4. Circumference: Multiply the diameter by π (3.14):
   
   • 3.14 × 34.8 = 109.3 inches
     
   • This helps determine revolutions per mile and affects speedometer readings.
     

These calculations confirm the tire’s key specs: ✔️ 12 inches wide
✔️ 34.8 inches tall
✔️ 109.3 inches in circumference

This size ensures a great balance of comfort, stability, and off-road performance.

Comparison with Other Tire Sizes

When choosing the right tire size for your vehicle, it’s essential to understand how different options compare in terms of performance, size, and suitability for various terrains. In this section, we’ll explore how the 305/70R18 tire stacks up against two other popular tire sizes: the 265/75R18 and the 33×12.50R18. Each of these tires offers distinct advantages, and understanding their differences will help you make an informed decision based on your specific driving needs.

305/70R18 vs 265/75R18

When comparing the 305/70R18 to other popular tire sizes, such as the 265/75R18, the 305/70R18 stands out for its wider tread, offering better grip and off-road capability. The wider tire also increases the overall height, which contributes to greater ground clearance, a key advantage in off-road situations.

305/70R18 vs 33×12.50R18

A common alternative to the 305/70R18 is the 33×12.50R18, which offers a slightly more aggressive look and enhanced off-road capabilities. While both tire sizes offer similar overall diameters, the 305/70R18 has a better balance of on-road comfort, while the 33×12.50R18 excels in off-road environments.

Tire Models Available in 305/70R18

The 305/70R18 tire size is available from several reputable manufacturers, offering tires designed for both off-road and highway use. Some of the top models include:

• BFGoodrich All-Terrain T/A KO3: Known for its durability and impressive off-road traction, making it ideal for trucks and SUVs.
  
• Yokohama Geolandar M/T G003: A robust tire with excellent traction on rugged terrain, ideal for adventurous off-road driving.
  
• Cooper Discoverer S/T Maxx: Designed for both on-road comfort and off-road durability, this tire is perfect for those who split their time between the highway and dirt roads.
  

These models come with various tread patterns that improve grip and handling, whether you’re navigating muddy paths or tackling snowy roads.

305/70R18 All Terrain and Mud Tires: A Quick Guide

When choosing tires for off-road and on-road use, 305/70R18 all-terrain and mud tires are popular options. Here’s a simple comparison:

All-Terrain Tires (305/70R18)

All-terrain tires are great for both highways and light off-roading. They offer a balance of traction, durability, and comfort.

• Pros: Good for gravel, dirt, and light mud; smooth ride on highways.
  
• Best for: Drivers who want a mix of off-road and on-road performance.
  

Top Models:

• BFGoodrich All-Terrain T/A KO2
  
• Goodyear Wrangler Duratrac
  
• Cooper Discoverer AT3 4S
  

Mud Tires (305/70R18)

Mud tires are designed for tough off-road conditions like deep mud and sand. They have aggressive tread patterns for maximum grip.

• Pros: Excellent traction in mud and sand; ideal for extreme off-roading.
  
• Cons: Can be noisy on highways.
  

Top Models:

• Nitto Trail Grappler M/T
  
• Toyo Open Country M/T
  
• Falken Wildpeak M/T

For all tire-related services, visit our tire repair page for expert assistance.

FAQs

1. How tall is a 305/70R18 tire?

The overall diameter, or height, of a 305/70R18 tire is approximately 34.8 inches (885 mm). This provides a solid ground clearance for off-road adventures.

2. How wide is a 305/70R18 tire?

The tire is 12 inches (305 mm) wide, providing a larger footprint for better grip on rough terrains and increased stability.

3. What is the significance of the aspect ratio (70)?

The aspect ratio indicates the sidewall height is 70% of the tire’s width. A higher aspect ratio like 70 provides better ride comfort and shock absorption, making it suitable for off-road conditions.

4. What vehicles are best suited for 305/70R18 tires?

These tires are ideal for full-size trucks and SUVs, particularly those used for off-roading or heavy-duty tasks.

5. Can I replace 305/70R18 tires with other sizes?

Yes, as long as the replacement tire’s size is within 3% of the original tire’s overall diameter. Sizes like 275/75R18 or 285/75R17 are good alternatives.