Will Oversized Tires Affect Gas Mileage?

A car tire’s diameter or size affects its fuel economy, braking, acceleration, and overall performance. But does it affect gas mileage, too? Let’s elaborate on the answer below.

Tire Size and Car Mileage

The quick answer is no, but a more detailed explanation is a little more complicated than a close-ended question. The reason being there are many situations where bigger tires do not increase gas efficiency. The rationales behind are the heavy weight and the larger diameter of the tire itself. The bigger and the heavier a tire is, the higher the rolling resistance, which means the engine and fuel have to work extra.

A car can gain or lose a good percentage of the gas economy by changing tire diameter. But various factors are affecting this, that’s why the answer to the central question in this post cannot be straightforward.

Gear

The gear keeps a car close to the peak torque RPM for maximum efficiency. Small tires cause the engine to spin faster to maintain speed, wasting fuel and power. On the other hand, large tires cause the engine to fall below its optimal efficiency range, needing more energy to stay running at peak RPM. 

Torque

Torque refers to a car’s turning power, and it is the most significant factor in how tire size affects fuel economy. A vehicle with more torque will provide more power to the tires as they spin. 

Vehicle Type

  • Diesel trucks and other cars that produce more torque than they need to maintain speed benefit from large tire diameters.
  • Tall tires raise a vehicle away from the ground, increasing its wind resistance and decreasing fuel efficiency.
  • Large diameter tires have a wider contact patch on the ground, which increases the need for power and gas to maintain speed.

Choosing Your Car Tires

Larger diameter tires increase a car’s fuel mileage if it regularly travels at a constant speed of over 60 miles per hour. Simply put, if a car drives on the highway frequently, larger tires make an excellent option. 

If you’re looking to achieve both fuel efficiency and bigger tires, you may need to do a lot of research and thinking on the tire you will be using in your car. The weight, type, size, thickness, and tread pattern of a car’s tires affect its gas mileage. On the same note, large diameter tires with low rolling resistance are more efficient than those with the opposite. 

Driving habits are also a consideration when selecting care tires. Some off-road tires can be more gas efficient than all-season ones. 

Final Thoughts

Will oversized tires affect gas mileage? As you’ve read, the answer is not as simple as a yes or a no. Small diameter tires aren’t always more fuel efficient than larger ones, and larger tires aren’t always less fuel economy. It all boils down to matching the tire size with your lifestyle, driving habit, vehicle type, frequency of use, and frequented type of road.