Ya, don't try driving around national parks with that; any given tree limb will take that down. It needs an exhaust-catching trailer equipped with an Oklahoma-style windmill pump to put the catchings back into the tank because of the wind you get when you move forward. There's a more ancient method where the car's wheels also turn a ledged screw which moves water up the screw and back into the tank. Now if you're going fishing in that thing, make sure you compensate for evap loss with makeup water from the lake.

Archimedes knew how it was done: