How can I clean my oven racks without them discoloring?

I usually put them outside on newspapers, spray liberally with oven clean and let sit in a warm area. Then flip and respray and let sit awhile. Then I put in the sink or use the hose and a brush to remove most stuff, if there are a few stubborn bits use a brillo soap pad. Respray any tough bits again if need be.

my favorite way is take a large plastic garbage bag.....put the grates in it after they are sprayed with oven cleaner....close the bag tightly. Let sit overnight.....hose off in the morning.

After the oven cleaning, I clean mine with sos and they are lovely. J.

goo gone rub on thick and let it rack set for awhile wash off with hot water

Avoid using bleach

I let them soak in a sink full of Dawn liquid and hot water. You can use the tub if sink too small.