2015 Silverado HD, Sierra HD Chevrolet and GMC today revealed the all-new 2015 models of the Silverado HD and Sierra HD full-size pickups, featuring segment-leading capabilities across the range including the highest payload – 7,374 pounds – and the highest conventional trailering rating – 19,600 pounds.
Silverado HD’s all-new exterior communicates strength and capability, while also enhancing aerodynamics for improved efficiency and reduced wind noise,  It also improves cooling for more consistent power under tough conditions.
The new Sierra HDs arrive in the first quarter of 2014, including 2500HD and 3500HD models, and the Sierra Denali HD, which matches do-it-all capability with an exclusive package of design and upscale interior amenities.
Additional new and enhanced features for the 2015 Silverado and Sierra HDs include:
CornerStep rear bumper, EZ Lift and Lower tailgate, standard upper tie-downs and other features that make cargo handling easier
Standard StabiliTrak with Trailer Sway Control on all models, including 3500HD dually
Integrated cruise control, auto grade braking and diesel exhaust braking (diesel models), for greater driving control and reduced brake wear on grades
Enhanced cooling airflow, which enables the Duramax turbo diesel and 6.0L gas engine to better maintain full power, even under heavy loads and high ambient temperatures
The 2015 Silverado HD and Sierra HD pickups will be assembled in Ft. Wayne, Ind. and Flint, Mich.
Source: GM