Anyone know this movie?

I think it was made in the 80's or early 90's. It takes place in a desert-like environment, possibly a post apocalyptic world. There is a guy who drives around in some dune buggy futuristic car and calls himself a ranger. Somehow the plot of the movie revolves around crystals. Bad guys are trying to get the crystals and the ranger tries to stop them. This was a long time ago, and my memory is a little hazy. It was kind of a cross between the road warrior (mad max), but with a sci fi edge to it. Any thoughts?