The all-new 2019 GMC Sierra Denali, the flagship of the next-generation Sierra lineup, is powered by an available 420 horsepower 6.2L V-8 engine paired with a 10-speed automatic transmission and offered as a crew cab has nearly 3 inches of additional rear-seat legroom compared to the previous model. The all-new Traction Select System allows drivers to choose from preset available drive modes that have been tailored for different terrain or weather conditions.
