Arizona exempts 5,000 for a vehicle (lucky you !). If you OWE 6K and its worth 6K, then you have NO EQUITY. However, you really need to check on that value, where did you get it ?? Use trade-in value and subtract from that any repairs it needs.
If you've missed payments and are past due when you file CH 7, you're going to have to catch up those payments FAST. If you're behind when you file, the bank will simply file a Motion for Relief from Stay to move forward with a repo, and the court will very likely grant it to them.