The best you could really do for the undercarriage is to wash it off with a hose under pressure to remove loose, caked on funk and *especially* road salt during those winter months.

Every time you wash the X, just hit everything underneath with a nice stream and wash it off, paying attention to nooks where mud and such can accumulate.

Rust down there is normal and more or less impossible to stop. But with a little care, you can prevent premature rusting of the body parts.

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