GM’s full-size 1500 series pickups are new for 2007. The GMC version is called Sierra (Chevy’s is the Silverado) and is differentiated from its corporate cousin by exterior and interior styling differences and higher trim content in most models. The ’07 Sierra is available in base work truck, SLE (SLE1 and SLE2 models), SLT, and top-of-the-line Denali trims, with either rear- or four-wheel drive. Three cab styles are offered: regular, extended and crew cab. Three bed lengths are also available — 5’8”, 6’6” and 8’. A Z71 off-road package is also offered. Some of the features found on the new Sierra include an available stadium-style rear seat with a 60/40-split design. It can be easily folded up to provide an uninterrupted load floor. Either section of the split seat can also be stowed independently, allowing room for both cargo and a rear-seat passenger. Entry to the rear seat/storage area of extended-cab models is eased with new rear access doors that open 170 degrees. The standard engine in the ’07 Sierra is a 4.3-liter V-6 rated at 195 horsepower; 4.8-liter (295 horsepower), 5.3-liter (315 horsepower), 6.0-liter (367 horsepower), and 6.2-liter (400 horsepower) V-8s are available. The 6.2-liter V-8 is standard in Denali models and unique to the GMC truck (not offered in its Chevy cousin). The 6.2-liter engine is also teamed exclusively with a new six-speed automatic transmission; the other engines come with four-speed automatics. Stability and traction control are standard across the line; head/curtain airbags are available on Sierra SLE and SLT models. Rear-seat DVD entertainment system, GPS, and heated steering wheel are available on Denali models.