I have had tires slowly leak, Slowly leak, and try though we might (And this included tanking it) we could not find the leak (This was on a car by the way)
Finally, it just stopped leaking.
My best guess, and I stress Guess is a bead leak that was sensitive to pressure on the tred, it only leaked when the right spot was down. and finally sealed.
Tire stores HATE SLIMR Green stuff you put in after you let the air out and before you air back up) and if you use any kind of TPMS forget it, But there are several sealsers that actually work.
Never tried 'em on big tire though, just cars and smaller.
