With winter here, and the salt being poured on the roads to such an extent that it looks like snow, its time to remember what salt, water, and metal combine to form. I hightly recomend taking the time to rinse off your frames or anything else that you have drug across the rocks, apply a coat of primer and paint. I myself have found that all the scraches are already rusting, so I'm in the middle of "preservation" right now. (as low as I am, i've drug just about every square inch of frame, skid, cross member, and diff over the past year + ) A few dollars in paint each season will allow your frames, skids, diffs, cross-members, oil pans, etc to last much longer in these car-unfriendly New England winters. I'm hoping to never have to be part of the toyota rust recall.