Cars.com has updated its American Made Index, and the list has flip-flopped some models right off, while others have hopped onto the top ten. Cars.com uses the parts origin information from the window sticker, along with the location the vehicle is manufacture at and sales numbers to determine which vehicles have the most US-based content. Ford's F150 and Explorer are the chocolate wafer to the rest of the list's cream filling, sandwiching everyone else between their respective #1 and #10 rankings. General Motors has the most vehicles in the top ten list, with the quartet of Cobalt, Malibu, G6, and Silverado 1500. Not surprisingly, Toyota's Tundra, built in Indiana and Texas, makes the grade at #5. Chrysler's Sebring is that company's only placing on the list, though even the same generation of a particular model can place high one year and fall off the next as automakers juggle OEMs and running changes. If sales of light trucks continue their precipitous fall, the AMI may look radically different the next time around. Four of the ten are body-on-frame trucks, and there's also a pair of minivans, all set to suffer in sales as buyers start to move en masse to more efficient vehicles.