This is driving me nuts (short trip)...I just purchased a new dishwasher and my aluminum pans are "staining". They change color--get sort of a film that doesn't wash out. This didn't happen with my old dishwasher--I have 20 year old pans that look brand new until now. does anyone know why this is happening?? Doug?? Are you also a metallurgical engineer?? I'll be eternally grateful is someone could solve this mystery.
Here's a discussion on aluminum pots in the dishwasher discoloring:
(Tips range from using less detergent, to using more Jet Dry, to inadequate rinse cycle.)
We have a store that I use all the time. It rents any and every cake pan you can imagine for like $3.00. There are signs all over that store that if you put one of thier pans in the dishwasher there is someting like a $25.00 fee. SO, I never put my pans or thiers in the DW. I am not sure why the film occurs but it is darn hard to get off.
I've stopped washing my pans in the dishwasher for this reason, no film on them but they were very discolored and I was very upset.
Thanks for the info, but I'm just not buying it!! I use the same water, soap---everything but the dishwasher is the same. I HAS to be the dishwasher--maybe the water is too hot--they seem to etch less if I don't use the booster heater. I'll continue my search!!