GMC Sierra Denali - Its about the numbers. The 6.6-liter, V8 turbo diesel engine boasts 397 horsepower at 3000 rpm, and an eye-popping, mother-lovin?, stump pulling, 765 lb-ft of torque at only 1600 rpm! And if you want bragging rights at the drag strip, you can reach 60 mph from a dead stop in just over 7 seconds and cross the ¼ mile in just over 15 seconds. All that power is put to the pavement