What effect does incorrect tire pressure have on a vehicle's fuel efficiency?

Incorrect tire pressure significantly decreases a vehicle's fuel efficiency. When tires are under-inflated, they create more rolling resistance as they deform more when in contact with the road. This increased resistance means the engine has to work harder to maintain the same speed, leading to increased fuel consumption. Conversely, if the tires are over-inflated, they can result in a smaller contact patch with the road, which can lead to a loss of traction and stability issues, but might not directly correlate to fuel efficiency in the same way as under-inflation.

Maintaining proper tire pressure is essential not only for optimal fuel efficiency but also for tire longevity and overall vehicle safety. Regularly checking tire pressure can help drivers achieve better fuel economy while ensuring they experience better handling and ride comfort.