Back while I was in high school and working for a local gas station. The station owner had installed a waste oil furnace, it worked great. It also burnt about 4-gal of oil a day because the garage doors were always being opened.


Waist oil is a good useable fuel, but I don’t see the few gallons you have as very useful to you.

I don't know how useful 5-gal of any oil be without an ongoing supply of it like waste oil is an ongoing free supply to a auto repair shop? they get it for free and it's endless to them.