Not sure if you have ever had your vehicle detail by a professional shop,the acid wash is how they remove the coat of wax on your car.... unless you know of another process to remove wax?Perhaps you 'scrape it off with your thumbnail"?
While I do not know the composition of the wax removing compound I would assume its not Sulfuric Acid (btw the correct spelling )which would be far too corrosive.
My Titan is white, an shows rust very plainly (small pin prick sized specks of rust)that results after 4 months of winter driving ,the 'grader dust' is not in the paint or clear coat but embedded in the wax,every spring I take my truck in an have the wax removed and rebuffed an waxed professionally,the paint which looks new an NO rust at all after 5 years of Canadian winters.
And I see your 40 years an raise yours too 42 years of driving,and I had never heard of it either until it was pointed out to me by a very good Dealership in southern British Columbia and a detail shop that explained how these small specs of rust can spread from a small metal filings off a grader blade to all out body rust from ignorance of a piece of knowledge someone was kind enough to inform me about before it resulted in major body rust,how else can you explain chrome rusting with out a catalyst?
There is an old adage about Old dogs an new tricks, keep an open mind , and maybe go outside an look very carefully at your paint specially the driver side where mud an snow and the other crap that splashes up from other cars passing you on the highways you may be surprised, or need a new pair of bifocals.
If you would like the shop that details my truck an bike,I'll be more then happy to give you their name,or perhaps you can spend $300 an get your vehicle detail an ask your detailing shop a little more about this subject.
Google is an amazing tool try it sometime before you lol @ something ,ignorance is no excuse to quote a smRt man.
Tiny Rust Spots...Brake Dust?? - Club Lexus Forums
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