Again, from Wikipedia:
“The 2005 Cadillac DTS limousine is a hand-crafted, custom built, armored version of the stretch Cadillac DTS built on a GM four-wheel drive platform.[19]”
So even the previous version wasn’t really a DTS, just a lookalike. Again, the DTS platform is completely unsuitable as a true armored limousine, as it lacks a true body-on-frame design, and thus is incapable of supporting the weight of the armor and other upgrades.
Hmmm.. From this article: http://www.netcarshow.com/cadillac/2006-dts_limousine/
“The 2006 Cadillac Presidential Limousine is a hand-crafted and armored version of the Cadillac DTS (DeVille Touring Sedan) stretch sedan for the President of the United States.
The new Cadillac DTS was first utilized during the second inauguration of George W. Bush in the January 20, 2005 parade.
The vehicle was custom built by O’Gara, Hess, and Eisenhart, armored vehicle builders who have been building armored presidential limousines since the 1960s. The base platform is a Cadillac DTS, but little of the original vehicle remains. For example, DeVille’s flush-style door handles have been replaced by a loop-type design apparently borrowed from the 1992-99 generation Buick LeSabre, doubling as grab-handles for the Secret Service agents running alongside the car. Exterior examination suggests that the head/tail lights, and the wreath-and-crest emblem atop the grille are some of the few stock components.”
And
“his is the most heavily armored presidential vehicle to date. The jet-black skin has 5 inches worth of ballistic armor, and is said to be able to withstand anti-tank grenade launchers. The underside of the car is also armored. The windows, which do not open, are transparent armor thick enough to block sunlight, which is the reason the interior is illuminated with fluorescent lighting. The vault like doors require automatic systems to open. Any casual observer can see the rolling fortress with the white rims on the tires, completing the armoring with a run-flat tire system. The limousine is also environmentally sealed against chemical and biological attacks.”