The 2011 Chevrolet Silverado 1500's Vortec 5.3L V8 FlexFuel (LMG) engine (Compression Ratio: 9.9:1) comes with 315 horsepower at 5,200 rpm (gas), or 326 horsepower at 5,300 rpm (E85). This particular engine also has 335 ft-lbs of torque at 4,400 rpm (gas), or 348 ft-lbs of torque at 4,400 rpm (E85).
The 2011 Chevrolet Silverado 1500 comes with the Hydra-Matic 4L60 four-speed automatic transmission or the Hydra-Matic 6L80 six-speed automatic transmission. The Vortec 6.2L V8 FlexFuel (L9H) version (Compression Ratio: 10.5:1) also produces 403 horsepower at 5,700 rpm, with 417 ft-lbs of torque at 4,300 rpm. You can also get the Vortec 5.3L V-8 FlexFuel (LC9) engine with this truck as well, which produces the same horsepower as the Vortec 5.3L V8 FlexFuel (LMG) engine.
For the 2013 model year, the Silverado 1500 and its hybrid variant will receive a few minimal changes - the most notable of which are three new colors, including Deep Ruby Metallic, White Diamond Tricoat, and Blue Topaz Metallic. The Imperial Blue Metallic and Black Granite metallic colors have been deleted. In addition, the 2013 Silverado will get a set of all-terrain tires (rather than the on-/off-road units on the 2012 models) and a few LPO options are discontinued, including the sliding bed divider, cargo management system rails, overhead utility rack, and the deluxe chrome package.
The changes are minimal in light of the new Silverado that is based on the K2XX platform that will bow for the 2014 model year.