Hola, and Happy New Year!
On the 2011Silverado, the "chrome" surfaces are likely several different material types:
• Chrome film vacuum formed over a plastic surface (think grilles, possibly the door handle covers and chrome mirror caps)
•Stainless steel (exhaust tips and likely the running boards and bumpers. Possibly the door handle covers.)
I am of the opinion swirls and scratches cannot be removed from "real" chrome plating - which is a hard, thin plating over a copper substrate. Like Mike, I've never seen it happen. Yes, you can hide it by filling, but a scratch is a scratch. I would not use a regular chrome polish on the chrome "film" - it will abrade through the surface after several application. Our
Mothers California Gold All-Chrome Cleaner is safe to use on this finish to clean, shine and protect.
Stainless requires speed to polish to a finish comparable to a chrome-like finish. That means using a tool (drill, rotary, etc.). You'll also need to multi-step with polishes to first remove the large scratches with smaller scratches (which is the definition of polishing) and then a finer polish or two to finish it off. We make an aggressive metal polish (
Mothers PowerMetal Scratch Removing Polish, metal polish, remove metal scratches) which works well as the first step.
Generally, window trim isn't chrome - it's commonly anodized aluminum. Anodizing is about impossible to restore without removing the anodized coating. It can also be stainless depending on the vehicle.
Are all of the surfaces on your Silverado you mentioned (chrome bumpers, running boards, mirror caps, door handles, and exhaust tips) factory, or were any of them installed by the dealer or aftermarket? If so, it's difficult to suggest a product/process since there are so many variables. Close up pics always help.