I've seen floors in aluminum stock trailers that have lasted 20 years or better. Semi trailers that haul cattle are also made out of aluminum and last a long time. The only reason for an aluminum floor to corrode is if the aluminum abutts a dissimilar metal and produces electolosis.
There's nothing like the Rockies in the springtime... Nothing like the freedom in the air... And there ain't nothing better than draggin calves to the fire and there's nothing like the smell of burning hair. -Brenn Hill