For 2010, GMC
has released then Sierra Hybrid truck. For the most part, the GMC Sierra wows reviewers with its combination of midsize sedan efficiency and pickup capability. Boasting a 40% increase in EPA city fuel economy, the new Sierra Hybrid can earn up to 21 mpg. For 2010, little has changed, though the one available engine, a 6.0 liter V8, is no flex fuel capable.