No, I don't think they would negatively effect your gas milage. You just need to make sure that you keep them with plenty of air. That is what would negatively effect your gas mileage.
Yes.
no
No
yes
If it is malfunctioning it can affect fuel mileage.
Roof racks themselves have a negligible effect on gas mileage.
Yes.Yes.
When looking into owning a gas mileage is an important factor. The gas mileage for a 1983 Buick Lesabre is 17 miles per gallon city and 24 miles per gallon highway.
Should have no effect
Drivers need to do everything they can to eek out the best gas mileage possible from their vehicles. Having the right size of wheels and tires, filled to the correct pressure, can make a big difference in the gas mileage a vehicle gets. Most vehicles have this information recorded just inside the drivers side door. This information may also be found in the owner's manual for most vehicles. When shopping for new wheels and tires for a car, be sure to purchase the sizes recommended by the vehicle manufacturer to get the optimal gas mileage the auto is rated for.
Yes. Alloy wheels are supposed to improve the gas mileage due to its low weight.
Only a minute amount.