The GMC Sierra 1500 is built on the same GMT900 platform as the Chevrolet Silverado and the Hummer H2, but versions of this platform are also the skeletons for the Tahoe, Yukon, Escalade, and Avalanche, making it the most profitable venture for GM by far. The Sierra is marketed as a more upscale pickup than its Silverado stablemate, with more luxury options available. Still, the similarities cannot be ignored, as decisions made for the Silverado reverberate over to the Sierra. For instance, the V8 turbodiesel the Silverado was scheduled to receive this year was cancelled due to financial considerations, which means the Sierra gets disappointed as well. That said, there’s no shortage of engines available to power the Sierra, with four conventional and one hybrid powerplants to choose from. Indeed, variety has always been the strong suit of both the Silverado and the Sierra, with a multitude of configurations to choose from, allowing the consumer to construct a full-blown workhorse or a utilitarian mobile office. There are three cab configurations (Regular, Crew, and Extended), three bed lengths (5.8-, 6.6-, and 8-foot), and two available 4WD systems, a base part-time 4WD that cannot be left engaged on dry pavement and GM’s Autotrac system that can, although both have a low-range gear for off-road duty. The 195-hp, 4.3-liter V6 that has served duty for GM for years offers 260 lb-ft of torque at 2,800 rpm and 15/20 mpg in RWD configurations, with 4WD dropping mileage down to 14/18. V8 power starts with a 4.8-liter, 302-hp engine producing 305 lb-ft of torque at 4,600 rpm. Surprisingly, the extra two cylinders don’t penalize mileage heavily, as the 4.8 still manages 14/19 with RWD and 14/18 with either 4WD system. While the previous two engines are mated to a four-speed automatic transmission, the remaining two conventional offerings get the benefit of a six-speed automatic, further bolstering fuel economy. The 5.3-liter V8 also gets GM’s Active Fuel Management cylinder deactivation, which along with the Xtra Fuel Economy (XFE) package leads to an impressive 15/21 EPA rating in RWD guise. The XFE adds several features designed to improve efficiency, like low-rolling-resistance tires and aerodynamic and mechanical upgrades. Without it, RWD economy is identical to 4WD at 14/19, which isn’t terrible for a power output of 315 hp and 338 lb-ft of torque at 4,400 rpm. For absolute brute force, the largest V8 is a 403-hp, 6.2-liter beast that offers 417 lb-ft of torque at 4,300 rpm, for a maximum towing capacity of 10,700 pounds. Mileage shows an EPA estimated 13/19 with RWD and 12/19 with 4WD, not exactly designed to impress. A 6.0-liter hybrid V8 is also available, producing 332-hp and a 21/22 EPA rating paired with a CVT. Buyers have the option of four suspensions, with the Z83 & 85 designed for on-road comfort, the Z60 acting as an on-road performance suspension, and the Z71 boasting off-road chops. Safety ratings are impressive, with the NHTSA awarding the Sierra 1500 five stars in all tests excepting rollover, which earned a four-star rating.