So what i am looking to come up as an idea is a tow mode/overdrive off. these modes appear on ford and Chevrolet vehicles and they disable the overdrive in an automatic transmission allowing for safer and more effective engine breaking. the only thing someone would have to do is change the behavior of the automatic transmission when the mode is engaged. Just like a modern column shifted automatic transmission. The mode is usually activated by pressing a button on the end of the column shifter. this mode appears on vehicles like the ford taurus, ford escape, and the Chevrolet silverado.