I 'R' not a chemist. But I've been using it diluted on the painted areas, and I see no spotting or corrosion from any over spray on the bare aluminum....
Did you catch the warning where I said make sure you dilute it 10 to 1? In the directions on the can, it says a 10 to 1 dilution is safe on bare metal, plastics, plexi, etc ...
Only the cleaner/degreaser. They make several products. You must get the right one.
https://www.krudkutter.com/index.php?option=com_products&task=product&pid=4&Itemid=62
[QUOTEALL PURPOSE (1½ CUPS OF CONCENTRATE TO 1 GALLON OF WATER):
Appliances; Mini-Blinds; Canvas; Chrome; Silver; Brass; Copper; Porcelain; Plastic; Fiberglass; Linoleum;
Aluminum; Vinyl; Patio Furniture; Walls & Baseboards; Carpets; Upholstery; Stainless Steel; Laundry Presoak; Wheels. ]