How big of a tire can you put on a stock F-250?

The Ford F-250 is a popular heavy-duty pickup truck known for its impressive towing and hauling capabilities. One common question among F-250 owners is how big of a tire they can safely install on their stock vehicle. The answer depends on several factors, but with the right modifications, you can significantly increase the tire size on your F-250.

Stock Tire Sizes for the Ford F-250

The Ford F-250 comes equipped with a variety of tire sizes, depending on the trim level and options. The most common stock tire sizes for the F-250 are:

• LT245/75R17


• LT265/70R17


• LT275/65R18


• LT275/70R18

These tire sizes provide a good balance of ride comfort, handling, and load-carrying capacity for the F-250's intended use as a work truck.

Increasing Tire Size on a Stock F-250

While the stock tire sizes are suitable for most applications, some F-250 owners may want to install larger tires for improved off-road performance, a more aggressive appearance, or to accommodate larger wheel sizes. The maximum tire size you can install on a stock F-250 depends on several factors, including:

• Wheel Well Clearance: The tire size is limited by the available space in the wheel well, which can vary depending on the suspension and body components.


• Speedometer Accuracy: Larger tires can affect the accuracy of the vehicle's speedometer and odometer, so you may need to recalibrate these systems.


• Gearing and Powertrain: Larger tires can affect the gearing and power delivery of the vehicle, potentially leading to decreased fuel efficiency and reduced towing/hauling capacity.

With the right modifications, such as a suspension lift kit and fender flares, you can typically install tires up to 35 inches in diameter on a stock F-250 without major issues. However, it's important to consult with a professional or do thorough research to ensure the modifications are compatible with your specific vehicle and meet any local regulations.

Conclusion

The Ford F-250 is a highly capable and versatile truck that can be customized to suit a wide range of needs. While the stock tire sizes are well-suited for most applications, there are options for increasing the tire size to enhance the vehicle's appearance, off-road performance, or other capabilities. By understanding the factors involved and making the necessary modifications, you can maximize the tire size on your stock F-250 and take your truck to the next level.

Are 33 inch tires the same as 285?

No, "33 inch" and "285" are not the same; "285" refers to the tire's width in millimeters, while "33 inch" refers to its approximate overall diameter in inches. A common "33 inch" tire is a 285/70R17, which has a diameter of about 32.832.832.8 inches.
 
285

• What it means: The "285" is the tire's width in millimeters (approximately 11.211.211.2 inches). 
• Other numbers are needed: The full metric size is written as 285/XXR/YY, where the first number is the width, the second number is the aspect ratio (sidewall height as a percentage of the width), and the final number is the wheel diameter in inches. 
• Example: A 285/75R16285 / 75 cap R 16285/75𝑅16 is about 32.832.832.8 inches tall, while a 285/70R17285 / 70 cap R 17285/70𝑅17 is also about 32.832.832.8 inches tall, but a 285/70R18285 / 70 cap R 18285/70𝑅18 is closer to 33.733.733.7 inches tall. 

33 inch

• What it means: This is a common, non-metric designation for the overall diameter of the tire in inches, which is helpful for off-roaders and a simplified way to talk about tire sizes. 
• No exact width: This number alone does not specify the width or sidewall height, so a "33 inch" tire could be a 285/70R17285 / 70 cap R 17285/70𝑅17, a 315/75R16315 / 75 cap R 16315/75𝑅16, or another size altogether, as long as the final diameter is close to 333333 inches. 
• Interchangeable term: While "285" is the width in millimeters, many people will say they have "285s" and mean a tire that is roughly 333333 inches in diameter, such as a 285/70R17285 / 70 cap R 17285/70𝑅17. 

What is the biggest tire you can put on a stock F-250?

The largest tire you can put on a stock F-250 without any modifications is typically a 35x12.50R18, which should fit without rubbing on most models. Some people have reported fitting a wider 37x13.50R18, but this may cause minor rubbing at full steering lock and might require some trimming, particularly with certain wheel offsets.
 
For a stock F-250

• 35x12.50R18: This size is known to fit on a stock suspension and wheel without any rubbing or modifications required, according to several user reports. 
• 37x12.50R18 or similar: This is often considered the absolute maximum. A 37-inch tire will likely fit, but may cause minor rubbing at full lock on the sway bar and the front fender liner. It is recommended to have the stock offset wheels to avoid additional rubbing issues. 

Considerations for your specific truck

• Model year: Tire fitment can vary between model years. For example, some 2017+ models have more clearance than older ones. It's always best to check with the specific model year you have. 
• Wheel offset: The offset of your wheels can significantly impact tire fitment. A stock offset wheel will provide the most clearance, while an aftermarket wheel with a negative offset will cause more rubbing. 
• Driving conditions: If you frequently drive in off-road conditions, you may want to consider a tire with more aggressive tread, which may require trimming or other modifications to avoid rubbing. 
• Tire width: For 37-inch tires, a narrower tire (like a 37x12.50) will have a better chance of fitting on a stock setup than a wider one (like a 37x13.50).
• The 3% rule: When replacing tires, it's best to stick to the 3% rule to maintain proper performance and safety systems. This means the new tire's diameter should not differ from the original by more than 3%. 

Will 35 tires fit on a stock F-250?

The short answer is yes! You can easily fit 35-inch tires on your 2021 Ford F-250 without needing any suspension upgrades or bodywork alterations.

Will 37 tires fit on a stock F-250?

No, 37-inch tires generally will not fit on a stock F-250 without modification. While some models (like the 2023+ Super Duty) have increased clearance, you will likely experience some rubbing, especially at full lock on the radius arms, sway bar, or fender liner. A lift kit, a leveling kit, and potentially wider wheels or different offset wheels are typically required to fit 37-inch tires without rubbing.
 
Considerations for fitting 37-inch tires on an F-250:

• Leveling kit: A common solution is adding a 2.5-inch leveling kit to the front, which provides more clearance to avoid rubbing. 
• Width and offset: The tire's width is a major factor. Wider tires will increase the chance of rubbing on the radius arms and sway bar, even with a leveling kit. Using wheels with a negative offset (e.g., -12 to -18) can also help reduce rubbing. 
• Specific models and years: Some newer models, such as the 2023+ Super Duty, have improved clearance and can more easily fit 37-inch tires, sometimes even without rubbing depending on the tire width and wheel offset. 
• Steering components: It is recommended to upgrade steering components, like the steering stabilizer, when fitting larger tires. This can significantly improve your truck's control and prevent premature wear on front-end components. 

What to expect without a lift

• Rubbing: Even with just a leveling kit, you will likely experience some rubbing, though it may be minor and considered acceptable for the look. 
• Steering limitations: Turning at full lock will cause the tires to contact suspension components. 
• Minor modification: Some minor trimming of the fender liner or other parts may be necessary to prevent rubbing issues. 

In summary, while it may be possible to fit 37-inch tires with a leveling kit and careful wheel and tire selection, a stock F-250 is not designed to fit them without modification.