Well i know for a fact that if you tell them u dont want the car anymore they wont officially take the vehicle untill you are 3 months behind and trust me i have done this twice and both times they pick up the car after 3 months of missed payments and auction it off and them u pay the difference of the balance of the car  and it gones on ur credit report as a repo but after a few months you can get another car loan for sure hpoe thisa helps u