Rams with rust
funny thing about aluminum... when bolted to stainless steel, & in the presence of clorine, the galvanic processes cause it to oxidize much faster than when there is not clorine present.
road salt will do a number on those ford pickups if there are stainless steel parts next to the aluminum
when two different metals come in contact, a small but measurable voltage is created.
http://aluminumsurface.blogspot.com/2009/04/corrosion-between-anodized-aluminum-and.html