I got this tank from a buddy who intended to use it for a smoker build. He got it from a maintenance shop who drained some kind of oil in it. Kind of smells like gear oil. The spigot looks pretty gnarly so I'm sure the inside is too, it's been mostly drained of oil and sludge. I'm going to lift one end up with an engine hoist and drain anything left into a bucket. I suppose I have some reservations on how to get it A) clean enough inside I can cut on it (I know people often fill with water) so that I can burn a wood fire in it and B) if I can even get it clean enough I'll want to cook on it. I thought if I managed to get a good fire burnout on it, I'd have ever the inside and outside sand blasted...but that first requires cutting a door. First post, apologies if this is a beaten to death topic but most of the posts I was able to find were tanks that held heating/fuel oil. Thanks!