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Tale of Two Mondeos

GM’s Hybrid Strategy: Start With Trucks and Work Your Way Down

Adweek reports on the coming debuts of hybrid SUVs from GM and Ford.

“Everyone is entitled to play to their strengths, and ours is in trucks,” said Ken Stewart, GM’s marketing director for new ventures. “If you want to get a lot of hybrids on the road, you put them in vehicles that people are buying now. Americans like trucks more than they like small cars. So our strategy is to start with the bigger vehicles and work our way down, which also has the most benefit for society, because the bigger trucks consume the most fuel.”

Hmm. While there is something to be said for that argument—targeting high-volume vehicles with high fuel consumption—the reality of GM’s rollout is a bit different.

The new Silverado and Sierra hybrids are not full hybrids, as is the Prius, and as is Ford’s new Escape SUV. Rather, they are “mild hybrids”— they replace the conventional electric starter and alternator with a compact electric motor, which also supplies power to the transmission. There is no hybrid drive; the gas engine is always responsible for propulsion. Full-hybrid systems, on the other hand, can drive on electric power alone until the batteries need recharging at which time the gasoline engine restarts.

That’s not to discount the advantages of what GM is providing. The new hybrid pickups do use regenerative braking to recharge the batteries; they keep the HVAC system running when the engine is shut off; and they do provide external auxiliary power (four 120-volt, 20 amp outlets).

But as a result of the use of a mild instead of a full hybrid design, the overall fuel savings are less. The Silverado and Sierra hybrids will provide 5-13% better gas mileage over the gasoline models. That’s not insignificant, but it is significantly less than the 40% improvement seen in full hybrid sedans, and the 20% improvement on diesel mileage seen in GM’s own prototype military diesel-hybrid truck. The EPA pegs Silverado/Sierra hybrid mileage at 17/19/18 city/highway/combined. This is indeed a gas savings; but these trucks still are heavy drinkers.

GM is breaking ground in the US by deploying hybrid pickups, but it could do much more. (And we’ll have to see how many they build.) Full hybrid pickups and SUVs. Diesel hybrids! If it did more, then not only would the marketing argument above be accurate, GM would clearly be positioned for revitalized leadership of a more fuel-sensitive market.

Information from GM on the Silverado and Sierra Hybrids here. Information on mileage and climate change emissions of hybrid vehicles here.


Jamais Cascio


I'm a little unclear about the use of the "full hybrid"/"mild hybrid" comparison, as the only other places I've seen that terminology used have been in Toyota press releases (and magazine articles that are the functional equivalent, such as the April 2004 Technology Review cover story on hybrids), which refer to the Prius hybrid tech as "full hybrid" and the Honda tech as "mild hybrid."

As the Honda Insight gets better mileage than the new model Prius (and the Honda Civic Hybrid gets better mileage than the older, but still "full hybrid," Prius), the "full/mild" distinction, in the Toyota usage, seems more like a marketing than a technology distinction.

The more neutral terms (which also seem more clear, at least to me) are "parallel hybrid" and "serial hybrid" -- parallel being the Honda system, where electric power & gas power are always available, and serial being the Toyota system, where electric power & gas power are sequentially available.

All this doesn't detract from the point you're making here, as it sounds like GM is not putting the electric motor to use in any propulsion aspect (unlike both the Honda and the Prius). I only raise the issue because "full" and "mild" have entered the hybrid car discussion as meaning something different from how you're using them, and I wanted to make clear the distinction.


Jamais, you raise a great point and I agree fully. Having a clear and consistent technology/product taxonomy is important for consumers -- and for the manufacturers. With hybrids, we're not quite there yet. Forget about the manufacturers. We even have academic and research groups as diverse as Argonne, Berkeley and the Technical University of Berlin using "full", "mild", "serial", "combined" and even "micro" as descriptors of the different types of hybrid configurations and results -- and in some cases, in slightly different ways. Very confusing indeed!
I'll do my best to find, or to clarify -- and to adhere to -- a consistent framework that maps to both the engineering distinctions and the increasing popular usage of different terms.
Thank you!
(And you're correct -- GM is not using the electric motor for propulsion.)

Jamais Cascio

Of course, one result of the taxonomic confusion is that it allows GM to get away with calling the truck a "hybrid" -- because, broadly speaking, it is -- while letting consumers think it's the truck version of the Prius.

Douglas Hvistendahl

Note that the electrocharger (search on that to find it) allows the GM type setup to be put into practice on a pre-existing vehicle. Also, it should be possible to design a serial/parrallel hybrid by putting the electric between the IC engine and transmission with an additional clutch between. It would be nice to see this with a high efficiency diesel engine involved.

Mike Sharon

Well they a hybird that is not 4-wheel drive.I would to buy a pickup diesel hybird,1/2 ton.

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