If the scratch is through the finish to the aluminum, filiform corrosion can begin there and spread under the finish creating an nasty looking area.
Occasionally we get a nick or scratch. I touch the scratch will CorrosionX preventative, wipe it off good and carefully cover the scratch with clear acrylic with an acrylic scratch pen, available at most auto centers.
If you're certain the scratch is not through the finish, you may want to polish the area with polishing wax, but the area may become more glossy than the surrounding finish.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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