Since you are taking a deduction based on an alternative to actual expenses the sale doesn't matter. If you were taking actual expenses you would also need to record the actual sale income or loss. Using the mileage deduction method it won't matter what vehicle you use, so selling one vehicle and replacing it for another will not effect your deduction. It's still 54 cents per mile in 2016, 53.5 cents per mile in 2017.
