Truck has been sitting in the yard almost 2 years. I was surprised to see the light actually come on. Figured it would be a funny thread. Folks may think twice after they make that "better check your headlight fluid" joke
It is low as stated above, better add some or your muffler bearings will end up failing. Then that one thing that does something will go all "screeeeee"...you know that one do-dad.