Ok, so my 1991 Jeep Cherokee Laredo is burning oil, as stated. I figure it burns a little less than half a quart every 200 or so miles. I always just figured older vehicles burned oil, but is it something more serious? Also, just the other day I checked my dipstick and there was a creamy white substance on the end. Not much, just at the tip maybe 1/2 a centimeter up. And I've got this clanking noise when I start it up. It sounds like its right near the radiator, like a clank clank clank. Any ideas??