do you think max had a secret storage place anyhere in the wasteland?

It's possible, though I'd imagine having somewhere to go back to would feel like an attachment to him, and that is what he tries at all costs to avoid.

Not to mention all the new tires, seeing as he's so careless with them.

in fury road, which i don't really consider cannon, they say on his tattoo that he has no guzaline and no supplies. i would think max has some guzaline stored away somewhere in a bunker or something.