The 2005 GMC Canyon is available as a 2-door, 3-seat regular side. Starting at $21,350, the 2005 GMC Canyon SL w/Z85 Heavy-Duty 4x4 Extended Cab is powered by a 2.8L , 4 -cylinder engine mated to a manual transmission that returns an EPA estimated 19-mpg in the city and 23-mpg on the highway. The top of the line 2005GMCCanyonFleet 4x2 Extended Cab , priced at $ 16,790 , is powered by a 2.8L , 4 - cylinder engine mated to a manual transmission that returns an EPA estimated 21-mpg in the city and 27-mpg on the highway.