Longer and longer car loans are creating an illusion of affordability that could lead to disaster in the event of a downturn in the economy. Most new car buyers consider only the monthly payment, not the total amount they will spend on that shiny new SUV or how long those payments will last. When the payments outlast the vehicle, more and more borrowers (nearly a third of them, at last count) roll over the remaining balance into a new loan, creating perpetuity of debt for themselves.