Gearing up for the big day on January 20th, I took a look into the past. Lots of changes over the years! From CBS News: "The 2009 presidential limousine provides the Secret Service with a valuable asset in accomplishing its protective mission by affording its occupants the highest level of protection," a statement from the United States Department of Homeland Security read. The 2009 Cadillac Presidential Limosine has run-flat tires, a sealed interior to ward off a chemical attack and more bulletproof glass area than past presidential limosines. "It looks different [from past models] and it is different in some ways, but it's pretty subtle," General Motors spokesman David Caldwell told Hotsheet. "Although many of the vehicles’ security enhancements cannot be discussed, it is safe to say that this car’s security and coded communications systems make it the most technologically advanced protection vehicle in the world,” said Nicholas Trotta, Assistant Director for the Office of Protective Operations. CBS News White House correspondent Mark Knoller reports that the new limousine is the first of seven that were ordered from Cadillac by the Secret Service. In a radio interview with CBS News, Secret Service Director Mark Sullivan calls the new limo a "state of the art vehicle that gives the highest amount of security and safety to the occupants."
Probably the most famous Presidential limo in history is the Kennedy Lincoln Continental.
Eisenhower had different car styles for different reasons. President Eisenhower's 1950 Lincoln Cosmopolitan.
1952 Chrysler Imperial Presidential Parade Car
The New York Times has a great Collectible Car slide show and history. Hail to the Chief!!