My old '91 flatbed was being run on WVO.
It's GARBAGE, don't do it!
As far as WMO, also GARBAGE.
I've heard people call it "Black Diesel".

IMO, if after all that filtering and running it through magnets and it still has a dark color to it, it still has carbon deposits in it.
I'm also totally against ATF, which is a friction modifier, ergo NOT A LUBRICANT!!!
Think of the tiny holes on the injectors when this crap runs through them.
WAFs (Waste Alternative Fuels) are a nice idea, but if they were viable, don't you think the government and oil companies would already have a supply line and taxation figured out?
Mark.