So you have a new vehicle and it needs DEF? Are you like, wait, what the heck? I bought this vehicle because it is supposed to be more eco-friendly and now I have to add something else to it? Come on.
So, what is DEF? Diesel Exhaust Fluid. If you need it, start looking for it, and maybe keep a container of it in your garage, because your newer diesel vehicle will more than likely need it.
When I borrowed a friend's truck over the weekend, I saw that it had a fuel gauge and a DEF gauge. While I sort of figured out that I go to a gas station for the diesel fuel, I had no idea what this DEF thing was and if it was a big deal or not to be slightly at 1/4 of it, and touching a red zone.