I have the stock exhaust tips, you know, the ones that are rectangle shaped. Well, after I got reared last summer, I got a new pair, and they were nice and clean looking. Now they are blackened by the exhaust.

To clean them, can I use some sort of degreaser, or what?

i think thats carbon, so you would need a product that gets rid of that. Try finding some solvent for it.

I would guess that a chrome wheel cleaner would work. armor all quiksilver is good at taking off brake dust. Could work in your situation

just make sure that you know what metal you are working on. It might be worth it to buy different tips if this is going to keep happening every couple months...

All depending how old the carbon is. Sometimes just taking hot water with some dishwasher soap(Joy) will do the job while using a scrub brush.

Where did u get your stock tips from. I lost one of mine backing into a snow bank. Are they expensive?

The body shop got them when they replaced my bumper. So I don't know.