GM launches a new generation of small pickup trucks with the 2004 Chevrolet Colorado and its GMC Canyon companion. Colorado is slightly larger than the Chevy S-10 it replaces and comes in regular-, extended-, and crew-cab body styles. Colorado and Canyon differ in trim details but share a platform and introduce two new GM truck engines. Replacing a 120-hp 2.2 liter as the base 4 cyl is a 175-hp 2.8. Supplanting a 190-hp 4.3-liter V6 is a 220-hp 3.5-liter inline 5 cyl. Both engines have dual overhead cams vs. overhead valves and come with manual or automatic transmission. Both are available with rear-wheel drive or with 4WD that has low-range gearing but must be disengaged on dry pavement. Canyon's regular cab seats up to three. Its extended cab comes with dual rear-hinged back doors and seats up to five. The 4-dr Crew Cab seats up to six. The Crew Cab has a 5-ft-long cargo box, the other models a 6-ft bed. ABS is standard. Available for the first time on a GM pickup are head-protecting curtain side airbags that cover all seating rows. Available on all body styles and with 2WD and 4WD is the elevated-ground-clearance Z71 off-road suspension. The ZQ8 sport-suspension option is a Chevy exclusive and includes 17-inch wheels vs. 15s and comes only with 2WD. A locking rear differential is available on all Colorados. Traction control is a new option with 2WD. Also available are leather seats (crew cab only), OnStar assistance, and satellite radio. Sold alongside Colorado for the '04 model year are heldover S-10 crew cabs.