You can claim all of your expenses, gas, vehicle depreciation, insurance, oil changes etc or you can claim your mileage. Claiming mileage is easier but if you add up your expenses and it's more than you should claim expenses instead. You can buy Intuit's Turbo Tax one year and let the program figure it out for you and then do your own taxes going forward for free if you're so inclined. After entering all of your expenses, it will tell you if you're better off entering expenses or using the standard mileage deduction.
This is what Turbo tax says, among other things: Whether to use the standard mileage rate or actual costs is a numbers game. Generally, the more economical the vehicle is to operate, the more likely it is that the standard mileage rate will give you the bigger deduction. Conversely, the higher the operating costs, e.g., gas, repairs, tires, etc. the more beneficial the actual cost method is likely to be.
Here is Turbo Tax's info: [
turbotax.intuit.com]