I am sure you can trade it in but it is an older car now so not all dealers will be interested. I suspect you will lose a lot on money if you do so as you will get bottom dollar for your car. If it is a good car I would keep it and get my money's worth out of it.
Sure, like F_O_R said. but if you really want a new one, dealers can pay off the old car for you and you would receive that amount less, the trade in value.
Unless you put a big down payment on it you will probably find that you don't end up with enough to pay off your loan.
Been there , done that and it is stupid to do so.
The dealer might add the deficit on to your new car loan which will make your payments really high and you will be even more upside down than before - viscous cycle!
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