Thanks kcward but if you look at my first post, I already tried Back to Black.
I am just going out and ordering new rails. The only problem is Having to remove my Roll N' Lock bed cover to change them. Not really a problem just more of a pain.

 

Like most problems, throw some money at it and it will go away. Bought new bed rails (both sides and tailgate). It was a little bit of a pain having to take off my Roll N' Lock bedcover to install them but because I'm neurotic about my truck, it was worth it. Thanks

 

Sweet... now don't ruin these!

 

My apologies ! I guess I read what I wanted to read, then shot off a reply!
For the record, the Back to Black works real well on my running boards, but not as well on the bed caps. I have been a little sloppy with the wax and have residue on them. The Back to Black doesn' take care of it.

Another option is to go to an Autobody supply store and get some plastic cleaner there. Use the pre-paint stuff. Dupont used to have a real foul smelling stuff that had vinegar in it (Acetic acid). It appears that your situation may be calcium carbonate (hard water).

For what it's worth!
Regards,
Kevin

 

For those who haven't bought new one's, Black Magic also works well. I didn't see anyone mention it but I've used it in the past and it works really good. FWIW.

 

I have the same problem as described in this thread. I have used nothing but Back to Black on them. I have never put anything on my bed rails that would cause abrasion. On the tailgate rail, the only spot is where my hand goes when lowering or raising the tail gate. Strange.

Back to Black does not even cover this up anymore.