True story. Remember all the jokes about blinker fluid, headlamp filters and muffler bearings you'd play on the girls or the newbies in auto shop class?
Well, Ford has a product called "exhaust fluid" labeled as just such, with an official Motorcraft part number. We have some at my dealership as of today.
Seems that with the new super strict federal emission requirements on diesel pick-ups, Ford's engineers got busy and came out with this stuff. It's basically water based LOADED with urea and ammonia from what I understand(sure smells like it). It has to be put in it's own separate tank just like an oil injected 2-stroke. But it's injected into the catalytic converter to aid in complete combustion of exhaust gasses. Ford says you're supposed to fill this tank every oil change/3,000 miles.
So there you have it, there is such thing as exhaust fluid. Things have sure changed from the days when you could bolt your carb off the chevelle right on the barracuda, make a minor linkage adjustment and you were GTG.