Diesel exhaust fluid is a thick blackish liquid used to minimize exhaust air pollutants produced by a diesel engine, such as carbon monoxide, hydrocarbons, nitrogen, and particulate matter. In short, diesel exhaust fluid reduces the number of pollutants produced by the diesel engine's combustion process, thus making it more environmentally sound. Now, why would anyone want to use this particular kind of fluid inside of their engine? The answer is simple. Diesel exhaust systems are typically much more extensive than those that run on other types of machines, and they...