The eAssist mild hybrid system is dead, long live the eAssist mild hybrid system?

With continually rising corporate average fuel economy levels required through 2025, General Motors will test a third generation of its eAssist mild-hybrid system during the current model year.

This time, though, they're not sedans and small SUVs. They're full-size pickup trucks, some of the highest-volume and most profitable vehicles GM sells.

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A few hundred 2016 Chevrolet Silverado and GMC Sierra pickup trucks will be offered with the latest eAssist system, to get driver feedback and market reaction, according to simultaneous press releases yesterday from Chevy and GMC.

The numbers are small: 500 Silverados and 200 Sierras this year, against 2015 sales of 530,000 and 212,000 respectively for the pair of pickups.

This time, eAssist is being applied to the 5.3-liter V-8 that's core to the pickup truck line, rather than the four-cylinder engines it was used with before.

2016 GMC Sierra 1500 eAssist

2016 GMC Sierra 1500 eAssist

Significantly, though, the addition of eAssist will cost buyers just $500--and will deliver a projected 2-mpg increase in EPA fuel-economy ratings, from 18  to 20 mpg combined.

And it gives GM bragging rights for the highest fuel economy of any V-8 full-size pickup truck.

Only a single version of each truck will carry the eAssist system: For 2016, it's offered on only the Chevrolet Silverado 1LT crew-cab with rear-wheel drive and the GMC Sierra SLT Crew Cab (also with RWD).

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GM has received widespread kudos for its plug-in hybrid and battery-electric technologies (if not necessarily its marketing of the cars that use them).

But the checkered history of the mild-hybrid system has largely been one of false starts and vehicles launched and then withdrawn.

Born in 2006 as the Belt-Alternator-Starter system, and applied to a handful of small and mid-size Saturn and Chevrolet models, the first generation was marred by a recall for 8,000 potentially leaky battery packs, the GM bankruptcy, and the death of the Saturn brand.

2008 Saturn Vue Green Line

2008 Saturn Vue Green Line

The second generation, renamed eAssist, arrived in 2012 on various mid-size and larger sedans from Buick and Chevrolet.

As with the BAS system, though, the EPA ratings of some of those models were quickly matched by improvements in standard gasoline versions--making them a more complicated and uneconomical alternative.

Those models were then withdrawn, and GM has gotten nowhere near the sales of 200,000 per year for the system that executives had suggested before the launch of eAssist.

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Still, the march of CAFE requirements continues apace.

With cheap gasoline only encouraging an ongoing market shift from passenger cars into SUVs and trucks, GM and other makers need every technique they can muster to boost the gas-mileage ratings of every vehicle in their lineup.

And GM's investments in its electric-car programs appear to pay off for the latest eAssist; Chevy noted that the 100-pound battery pack under the console between the front seats uses the same Hitachi lithium-ion cells as the 2016 Chevrolet Malibu Hybrid.

2016 Chevrolet Malibu Hybrid

2016 Chevrolet Malibu Hybrid

Given that the 2016 model year is already half-over, we suspect that the eAssisted pickups have already been made a permanent part of GM's truck ranges for future years.

It remains to be seen if improvements in gasoline models will follow the historic path and eat away at the hybrids' competitiveness from below.


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