The 2005 Cadillac CTS is available as a 4-door, 5-seat sedan. Starting at $32,440, the 2005 Cadillac CTS w/1SB/1SC is powered by a 3.6L, 6-cylinder engine mated to a manual transmission that returns an EPA estimated 17-mpg in the city and 27-mpg on the highway. The top of the line 2005 Cadillac CTS w/1SA, priced at $30,190, is powered by a 2.8L, 6-cylinder engine mated to a manual transmission that returns an EPA estimated 17-mpg in the city and 27-mpg on the highway.