In reference to this post...
https://chevroletforum.com/m_14434/mpage_1/key_/tm.htm

I have a '07 LTZ with the factory Chrome Grill, door handles, and side mirrors. I bought it just before our nasty winter we've had in Colorado and have washed the vehicle probably15 times since December. I have noticed that after numerous times of scrubbing the grill and mirrors there are still a lot of small discolored oxidation marks all over the chrome grill that won't wipe clean. I have even used a chrome polish to try and remove these marks which it did a pretty good job on the mirrors but not the grill. Does anyone have any recommendations or know of a good product to remove these ugly stains from the mag chloride?

 

Hmmm, have you tried neverdull? The silver aluminum can stuff, it is a cloth that you tear in pieces and rub on?? NOt sure it if will work, but it is a very good cleaner/polisher!

 

If I know Chev., then the chrome grill on the LTZs is probably vacuum plated plastic like the old Denali. If so, you need to be careful with what you use to clean/polish it because the plating is very thin. Same would be true with the handles and mirrors if they are plastic.

 

Will this work on aluminum?

 

Yes, all parts and pieces are definitely plastic chrome. 73shark - do you have any recommendations for cleaners? Have you tried neverdull that biglg is talking about?

 

Try "Mothers Chrome and Billet Polish"

 

There are 3 types:

Mother's Chrome Polish
Mother's Billet Polish
Mother's Plastic Polish

Which one of these should I use for the plastic chrome pieces?

 

No. I've used something similar (X-Treem) which seems similar to what biglg is describing. I think the thing you want to careful with is not to use anything abrasive if at all possible.

 

there is product called "ZOOP SEAL"
I've tried it personaly on many different chrome applications. it's actually works. problem is, not cheap.
here is link below for more info

http://www.zoops.com/zoopseal.asp

 

$80-$100 is beyond "not cheap". I looked into this stuff several years ago and was put off by the price. Probably very good tho.