https://www.reference.com/vehicles/happens-put-wrong-size-tire-vehicle-285c58ed137a51ed A tire with the wrong inside diameter may not properly fit the rim, while a tire with an incorrect outside diameter may affect the accuracy of the vehicle's speedometer and odometer. Additionally, because the traction control, torque and gearing settings depend on the distance the wheel travels in one revolution, a tire with the wrong outside diameter may also affect the proper function of these critical systems