The GMC Yukon Hybrid was the counterpart to the Chevy Tahoe Hybrid. And the GMC Sierra Hybrid was the sibling to the Chevy Silverado Hybrid. GMC was the only brand with an exclusive focus on fuel-sipping vehicles for people who work for a living and tow big things on the weekend, but these General Motors vehicles are now discontinued. A few years back we wrote: “The big question is how long General Motors will stand behind them. The Yukon and Sierra are impressive—although a bit pricey—attempts at a greener versions of the segment,” and that insight proved prophetic. What’s next? We’re not sure, and not sure General Motors is either. Actually an opportunity before its eyes is Oregon-based VIA Motors headed up by GM’s former Vice Chairman, and Volt backer, Bob Lutz. It takes GM trucks in Mexico and converts them to 100 mpg series hybrids. GM has expressed no interest in buying VIA, or copying the formula. It cold do it all cheaper, but so far is not.