We use a product called aluminun bright to clean and get the corrosion off the offshore tool boxes we have here.. ......On my old truck I had real bad water spots on all the windows.
Put on a pair of rubber gloves(you need that with this stuff) and dip a rag in aluminun bright and wipe (do not rub hard,no need to ) the whole window with it.
Will turn the window a cloudy color,let sit a minute, wipe off dry and your water spots are gone
DO NOT do this to the front windshield for some reason it stay cloudy and will not clear up,(How do I know this ??) Side and rear windows come out very clear just like new glass
Put on a pair of rubber gloves(you need that with this stuff) and dip a rag in aluminun bright and wipe (do not rub hard,no need to ) the whole window with it.
Will turn the window a cloudy color,let sit a minute, wipe off dry and your water spots are gone

