Larger tires can decrese gas milegage.
no
The manufacture of your vehicle designed the tires to give the best ride, handling, mileage, and overall performance. Changing this tire size will effect one or more of these criteria. Improved mileage may come at a cost of lost performance. The engineers spent many hours deciding on the perfect size for this vehicle. My recommendation is to stick with the OEM size tire that the engineers designed for your vehicle.
It does not change the actual speed of a vehicle but changing tire size can affect the accuracy of the speedometer.
if their the same tire size then yes
Marginally. Tire pressure has a greater effect! The harder the tire the better the mileage (but the ride is stiffer and the center of the tread wears out faster so it might be uncomfortable and economically a poor idea).
18" - 20" BUT WATCH TIRE SIZE!!
Understand that the primary function of tread on a tire is to divert water from beneath the tire to improve traction and avoid hydroplaning on wet roads.
A tire alignment is not necessary when changing tire sizes. You can tell by the wear on your previous tires if you need an alignment. If you have uneven wear, get an alignment.
The car is designed to have a certain size tire on it. The suspension is tuned for a specific size. Changing wheel or tire size changes all of the engineering that went into the suspension. The sidewall of the tire is what supports the weight of the vehicle. Using a bigger rim with a low profile tire will cause added stress to front end parts and will have a much harsher ride.
Depends on the vehicle. It could improve mileage or lower mileage.
Yes, it is possible, however changing tire size may effect your spedometer. The change of tire size to a smaller tire will decrease your ground clearance, although it will increase the torque to the wheels.
The answer depends on the size of the tire in relation to the original tire size. A tire with a smaller circumference will turn more at a given speed, which will cause a higher speed being displayed on the speedometer. A tire with a larger circumference will lead to a slower speed being displayed. The speedometer can be calibrated to correctly display the speed for a different tire size. Changing the size of tires on a vehicle will also change the way the vehicle handles and may cause faster wear on suspension components.