The 2012 GMC Sierra 2500HD is available as a 2-door, 3-seat regular side. Starting at $32,620, the 2012 GMC Sierra 2500HD SLE 4x2 Regular Cab is powered by a 6.0L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated The top of the line 2012 GMC Sierra 2500HD Work Truck 4x4 Crew Cab Long Box, priced at $36,185, is powered by a 6.0L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated