Brown tires

I have an set of tires that over time have discolored. Now even when I clean them, the formerly black parts of the tires (these are whitewalls) appear brown. I'm trying to decide what to use to get them looking black again-any suggestions?o No:

 

So far just soap and water with a good scrub brush. The tires are 13 years old (I know, replace them!) Other than the discoloration, they are in good shape-no dry rot at all.

 

Zud, it's kind of like Comet.

 

Put them bad boys into the recycle system, unless you only drive that car in parades! And then you'd best have a rack of spares. The outside discoloration isn't the only deterioration that is going on.

 

Westlie's Bleach White

 

Try an orbital sander with 320 grit paper. Be gentle and keep the sander moving. It works for me.

 

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