Cleaning aluminum bumper/shadowline?

[sonick]

My bumpers and shadowline are all cloudy and water-spotted (the latter is especially the case for the shadowline).

Scrubbing with car soap nor quick detailer will get rid of the water spots.

Anybody know what I should use to clean it? I hear they are clear-coated so regular metal polish would be ineffective.

Thanks!

[stevehecht]

I just went through a long investigation about this myself. Metal polishers don't work as you say. ClassicTrimCoat.com and Bavarian Auto (Part # : 07500100002) both sell (the same?) kit where you sand off the clear coat and re-apply a new coat. I've heard a lot of conflicting opinions about this product, but the clincher to me was a fellow on the BMWCCA forum who has been detailing 2002s, E28s, E30s, and E34s thirty years and said he'd never seen this product work successfully. So I dropped the idea. I priced out the trim pieces on Pelican and it came to around $300.

[M5wanaB]

clay bar.