I live in northwest NC and my father-in-law is looking for a used dodge. He found a '98 12-valve dually extended cab with 132,000 miles. It has a flat bed and a 5 speed. It also has an exhaust brake but the current owner says that it is not working b/c of a vaccuum problem. He wants 15,500 for the truck. Is it worth this? Thanks for any comments.