GM's full-size hybrid pickups, the Chevrolet Silverado Hybrid and GMC Sierra Hybrid, for much of the time they've been on sale, have offered the highest gas mileage of any full-size truck on the U.S. market.

Yet these hybrid pickups, which were introduced for the 2009 model year, have been surprisingly slow-selling. Total sales numbers for the GM [NYSE: GM] full-size hybrid trucks added up to just 3,114 last year, from a high of 8,797 across five models in 2009.

And now, we've received official confirmation that they're discontinued.

At a special event last week previewing GM's 2014 Chevy Silverado and GMC Sierra, GM North America President Mark Reuss confirmed to us that this so-called Two-Mode Hybrid system is no longer part of GM's plan for pickups.

New engines, but no more Hybrid

“In this truck we decided to go with the EcoTec3 technology, with the V-6 and the two V-8s, and we think that's the best solution for our customers,” said Reuss. “So with this next generation it will not be a hybrid.”

The information is expected, in light of several reports in recent months—one from GM Inside News—citing company insiders indicating that the system was to be dropped in some or all of its current models.

Reuss declined to comment on the future of the system in the company's SUVs, like the GMC Yukon and Chevrolet Silverado, which are both currently offered with the Two-Mode system and due later this year for a significant refresh as well. Some sources had as recently as a few months ago confirmed that the automaker was still planning to offer the system in a refreshed Cadillac Escalade Hybrid—a vehicle that's served as a green image-booster for celebrities and business leaders.

Possible in the Escalade, too expensive in other models?

Price is a likely factor in these trucks' poor sales performance. Although they offer excellent EPA mileage ratings of 20 mpg city, 23 highway—for a best-in-class 21 mpg Combined—as well as good performance plus respectable towing and hauling ratings, the Chevy starts at $40,885, while the GMC starts at $41,305 for 2013.

For 2013, the mileage-focused Ram 1500 HFE model is the first full-sizer to tie that 21-mpg Combined rating; and it has an MSRP of just $28,250. GM hasn't yet revealed gas mileage ratings for its full-size trucks, which get new technology including direct injection, cylinder deactivation, and variable valve timing for an all-new V-6 engine and two new V-8s. The new V-6 might not quite meet the mileage of the Hybrid, but it would be far more affordable, with sales numbers that would figure significantly into average fuel economy calculations.

The Two-Mode system represents years of engineering and development collaboration between General Motors, BMW, and the company then known as DaimlerChrysler. Yet the once-promising partnership largely dissolved several years ago, leaving GM as the sole proprietor of the system. Outside of these GM pickups, as well as the Chevrolet Tahoe Hybrid, GMC Yukon Hybrid, and Cadillac Escalade Hybrid, the only other new vehicle offering a related system from the cooperation is the 2013 BMW X6 ActiveHybrid.


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