Polishing Aluminum Diamond Plate

I'm sure this has most likely been discussed before.
I searched around on here and couldn't find much info.
So,
What is everyone using to clean/polish the aluminum diamond plate that is used on the fronts of most CT's as rock or stone guards?
I have a 2005 and while I try to keep it clean and waxed the aluminum in the front and toe kicks on the doors is starting to look really dull.
I checked with a local outfit that services large trucks and they offered an acid of sorts. When I read the instructions I was concerned it was more of a cleaner than a polish.
The guy assured me it would "brighten" my aluminum. But at almost $50.00 per gal. I held off. So here I am asking advice on the forum.
Many thanks,
Jeff in Western Md.
I searched around on here and couldn't find much info.
So,
What is everyone using to clean/polish the aluminum diamond plate that is used on the fronts of most CT's as rock or stone guards?
I have a 2005 and while I try to keep it clean and waxed the aluminum in the front and toe kicks on the doors is starting to look really dull.
I checked with a local outfit that services large trucks and they offered an acid of sorts. When I read the instructions I was concerned it was more of a cleaner than a polish.
The guy assured me it would "brighten" my aluminum. But at almost $50.00 per gal. I held off. So here I am asking advice on the forum.
Many thanks,
Jeff in Western Md.