So you should have added it as an asset in 2013 for whatever the purchase price was. In 2013 it either was 1) entirely depreciated by using the 179 deduction or 2) started a yearly depreciation schedule. The depreciation is based on the value of the asset, not what you owe on it. If you purchased for 20,000, that would be the value. It doesn't matter if you paid 20,000 or paid 1,000 and financed 19,000. Hopefully you reported the purchase price when you entered the asset (vehicle) not the cash-out-of-pocket only.
