We know rust in the east b/c of the extreme amounts of salt used and the frequent freeze-melt cycles.
My BJ70 was fixed 6 years ago; lower rear quarters and some touch ups here and there. I will have to get it fixed again this year, but it's not as bad looking as it was 6 years ago.
Here's what I do:
-I use Krown light oil spray in early February, before it starts to thaw (that's when the salt really begins to work). The oil is fresh during the thaw, then, when it gets warmer, the oil wicks into every nook and cranny. Krown does it; in Feb. there's hardly anyone going there so they take their time. Also, they're down to their full-time staff, so less chance of getting some rushed fill-in part-timer. On top of that, they can't stand to see so much salt on the truck, so you get a free car wash!
-in the fall, I get a non-drip heavy, sticky oil applied only as an undercoat. I don't like the non-drip applied within the body panels, especially before the cold weather, because I think it actually clogs some cracks, seams and drain holes allowing moisture to remain and go to work. The Krown remains inside those fine, narrow areas.
Keep the frame cleaned out and heavily goo-ed up. Don't allow any structural compromise anywhere, ever. Don't ever use anything that dries hard like the old Ziebart; it'll just trap moisture and accelerate rust.
Make sure there are no holes underneath. The typical spot is under the rear wheel wells at the very back. Holes there allow salty moist air to circulate up as far as the roof pan. This could be a major contributor to roof line and roof pillar rot.
There's so much goo under my truck in places, when welding underneath there's a risk of it catching fire. Seriously, you get to recognize when that glowing blob is just going to drip down on to your wrist.... believe me you learn how to move fast!
Cheers from sunny (finally) Ottawa.
