Kidney Grille Discoloration

My two front grilles have developed a brown/yellow discoloration on the inside of the slats (the chrome is fine). I'd love to see if I can clean them up before I go the route of buying new grilles. Any idea what to use? I've tried QD, 50/50 vinegar/water, and scrubbing, but nothing seems to be working. Any ideas, or am I stuck buying new ones?

Try soaking it in something idk if it will help but try it

jfo122 wrote

My two front grilles have developed a brown/yellow discoloration on the inside of the slats (the chrome is fine). I'd love to see if I can clean them up before I go the route of buying new grilles. Any idea what to use? I've tried QD, 50/50 vinegar/water, and scrubbing, but nothing seems to be working. Any ideas, or am I stuck buying new ones?

Potentially soak in a concentrated automotive degreaser. Go with a 'compatible product' for exterior 'trim' along with recommendation for mix ratio.

From the looks of it, may be stains from corrosive road salt/chemicals...
If so, even with clean-up surface appearance likely degraded, color nonuniform...still worth a try.