Ford is recalling over half a million F-150 trucks, its best-selling model, due to an issue with the powertrain control module that could cause abrupt downshifting and increase the risk of an accident. Ford has budgeted for warranty costs from recalls and it is not expected to impact quarterly financial results materially. Ford has led the US auto industry in total recalls for the past three years. While recall headlines can alarm investors, the direct costs are usually insignificant if issues are addressed promptly.