Anything that removes grease is going to cause rust after it comes off, because the grease is whats keeping the metal from rusting.

You can always fog the bare metal with WD-40 after you clean it, in fact WD-40 also tends to remove grease without harming paint.

I like Gunk or Simple Green. If you hook your hose up to hot water it works a bit better.


Paint & Body Shop moderator
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