Proportionally, the 4.8 takes more throttle to get it moving with the same vigor as the 5.3. It has a 7,500-pound towing capacity, not that much less than the larger engine. The leather premium seats in this workhorse are better than those in many luxury sedans. These engines vibrate so little they feel almost like overhead-cam units. The 6.0-liter engine is only available in the heavier 2500 series trucks.
All engines are more efficient than their forerunners.
The Sierra is mechanically almost identical to Chevrolet's Silverado. Physically, it has distinct hood, fenders and grille. The level of standard equipment is higher, as befits GMC's positioning as the premium truck. The wheelbase is 1.5-inches longer. A side benefit is that it should be easier and less costly to repair crash damage.