Stainless steel is hardly the answer to this problem! It's too heavy; it's too expensive; and it is NOT immune to rust!
Anecdote: The way I was introduced to the features of stainless steel, was when I took the rusted out
stainless steel burner from my upper end home BBQ to the local appliance parts/repair depot for a replacement. We are really lucky to have one of these facilities in our neighborhood. Anyway . . . I carried with me the same kind of misinformation regarding stainless steel as mentioned in previous posts. When I queried the knowledgeable expert on this issue:
Q. Hey! This burner is supposed to be stainless steel!! How come it's all rusted out!??
A. [with a knowing grin] It's
stainless!! It's not
rustless!!
And indeed: How many of us have had to replace a rusted out BBQ burner!
There's absolutley nothing whatsover wrong with normal un-stainless steel; the kind that is used for the manufacture of every automobile on the planet; and it serves marvellously well in that regard!! When appropriately sealed against the elements, instead of being converted into rust (ferric oxide), it will last forever!!
Over the years, shoddy penny-saving efforts on the part of Winnebago has given rise to major big-dollar expenses on the part of their customers. Winnebago customers with pre-mid 90's rigs were plagued with rusted out compartment doors. Fifty cents for paint on the part of Winnebago, would have saved customers thousands of $$$ in replacing compartment doors with more of the same!! :-\
As for the initial poster, the only reason you have experienced this kind of rust on such a late vintage vehicle, is because Winnebago chose to save a few cents by refraining from painting the effected parts. :-[ Winnebago did the very same thing with their windshield mounting clips. While Winnebago might have saved a few pennies my not painting the windshield mounting clips; their customers, in consequence, have been faced with paying thousands of $$$ for replacement windshields fractured by accumulated rust build-up on the mounting clips!
And has Winnebago ever done anything about addressing that problem??
NB: Knowing about this particular Winnebago deficit, has enabled me to avoid the inevitable consequence by embedding these clips in a prophylactic sea of grease!! After ten years: still no cracked windshields. 8)