The nationwide gas price average broke through $4 a gallon overnight, with diesel just shy of $5.50. So production of HD pickups, the thirstiest of the mass market models, is slowing down, right? Not at General Motors. The General has just added an entire day of production to one plant that builds the beefiest GMC Sierra and Chevrolet Silverado HD trucks, according to a new report. That’s an extra 20%, or around 1,100 trucks per day.
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