It has been more than a few years since I paid the car off, but Ford (at the time) had an option that allowed payment by credit card. I don't remember if it was limited to Chase (who I think was doing to back-end processing for online payments) or if it was simply a Chase product I was using to max miles on the card. There was some small fee associated with the practice, but it was a small flat fee, not a percentage of the payment.