When you sign for the loan, it spells out in the fine print whether it's "transferable" or not... and whether there are any fees applied if you transfer the loan and/or withdraw from the contract early.
Oddly, if you got your loan through a reputable (major) banking institution, you can typically transfer them with only a minimal fee. If you got your loan through a credit union, or a place that just does car loans, they'll hit you with major fees. And if you got it through VW Credit... I think they're fairly leanient about transferring the loan. But you really want to pull out your loan documents and check out your specific loan.
Probably the best thing that you can do is find out what the payoff is on the car that you are willing to part with, find out the value of the car, and if the payoff exceeds the value of the FAIR MARKET VALUE of the car, be ready to take a loss.
Interest is the biggest downside to an auto loan and the SOLE reason why I refuse to finance a car. If you pay the minimum carpayment, and you finance anywhere close the entire amount you pay for the car, you're likely to be up-side-down in the loan within a year or two.
If people can buy a car for less than your payoff they are probably going to go that route. If they can't get their own financing, that's even more trouble.