You quote two numbers for the pay off amount. But regardless of what the pay off is, I am not sure if a CU or a bank will let you roll that much negative equity into a new loan. The captive finance companies however will let you roll the negative equity into a new car loan. But again that depends on the residual value of the new car you are buying sometimes up to 120% of the MSRP. I would not mention being upside down on your current vehicle as that negatively impacts your negotiation power. Expect about $1000 less than Edmunds TMV you see on line being offered for your current vehicle for the negotiations to start.