The 2006 Cadillac CTS is available as a 4-door, 5-seat sedan. Starting at $29,270, the 2006 Cadillac CTS Base w/1SA 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. The top of the line 2006 Cadillac CTS Sport w/1SB, priced at $35,570, 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 26-mpg on the highway.