So is the boot missing or just ripped? Can you tell if there's any grease in it? You can add grease yourself to keep it going. I did that with my van but it never made any grinding noise, just a clicking noise when I turned. I dont think it's your cv making the noise. Maybe a bad wheel bearing or brakes? Jack the wheel up and see if you can grab it top and bottom(tire) and try to make it wobble. Any play would indicate bad wheel bearing. Although it can make noise without play also. You can check brake pads/rotor while your at it.