You can sell your car even though you still have balance

Tell the buyer, both you can go together to the bank which holds your title under lien. describe the transaction to a banker, in front of him/her, the buyer pay cash to you, you pay whatever the balance is to banker. banker gets the money, signs the title and gives it to you. you sign your name on the back of the title and fill up a BOS (bill of sale; some state does not require a BOS). turn it to the buyer. done. everything is done on spot.