The Hybrid Silverado did around that time. It was only available for fleet purchase and was only an option on the loaded models with leather end push button 4x4. I get the same 21mog highway on a mid level model and maybe 1 mpg less city. I put the second battery tray under the hood that thee diesel trucks use and a battery there so I have the extra power feature just not the generator/starter and no engine idle like the hybrid.