I'll definitely keep that in mind when I look at the undertray.
I will also be starting a dedicated thread about this:
I have an idea about the cause/path of this rust, and hope to offer some good preventive info to owners of newer cars (or cars that live in less salty winter environments) that haven't begun to rust...
yet.
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UPDATE: I've started a dedicated thread about Prius rust, here:
http://ecomodder.com/forum/showthrea...els-32527.html
.