I think you have a misconception about repossession -- even if the bank does come and take it back, that doesn't end your liability. They'll sell it at auction, use the proceeds to pay down the loan (and late fees and other penalties), but if there's still a balance left on the loan, you're still responsible for paying it.
If it's in as bad a shape as you described it, they'd get get little in an auction sale. And for that reason, they probably aren't even going to try to repossess it. If you got a typical long term loan (10+ years), you've probably paid around 20% of the principal or less, but the unit probably dropped more than that the day you drove it off the lot, now it's 3 years old and "more or less totaled" so there'd be no reason for the bank to come take it back.
Your best bet would be to check used prices, fix it up as best you can and try to sell it yourself, but you'll need to come up with money to pay off the loan balance to get the title, so that may not be an option. You'd almost certainly get a better price for it than the bank would get at auction.