Vanessa said her brother put larger tires on his truck and that would make for worse mileage. He wants to sell it to her but she wants the stock tires so the mileage will be better. How does that work? I know you would know.
Answers from the Automotive Experts
Dear Sandra,
Tire size will affect the speedmeter. If the tires are bigger, then you will actually be driving faster than the speedometer says you are. The bigger tire doesn't affect gas mileage unless they are not properly inflated, or they are so much bigger that there is a weight issue. By this I mean they are huge mud tires for the beach. If you live in a state that requires inspection, these tires may also not pass inspection.
Lori
I agree - using the stock tires will give you the best fuel economy and keep the odometer accurate too.