We have heavy, heavy soil here. We do wash equipment to make sure that wet soils are not left in the nooks an crannies of our equipment, but the idea that we'd have a frame rot away from rust.. that seems like a 100 year timeline issue to me. Combine hoppers need to be cleaned out every season and do rot away, put that's not a tractor frame.

The painting at issue always seems to be very cosmetic to me, painting the hood on a tractor doesn't extend its life.. but it might increase its resale value!