Wider tires can have a surprising effect on the amount of gas your car uses. If you're considering upgrading to wider tires, it's important to understand how it can affect your gas mileage. Although there are some advantages to having wider tires, such as improved grip and better handling, they can also reduce your car's fuel efficiency. The increased rolling resistance of wider tires means that they require more energy to move, resulting in decreased gas mileage. To maintain good fuel economy, consider other options such as regular tire maintenance and keeping your car in good condition.