"We can't provide you with any information related to future product technologies or timing."

That's the standard response from carmakers--in this case, from Kevin Kelly, GM's Manager, Electric Vehicle and Hybrid Communications--when asked a question they'd rather not address.

Our question was pretty simple: Please comment on a recent report of the rumored death--or long delay--of the Two-Mode hybrid trucks, which include three full-size sport utility vehicles from Cadillac, Chevrolet, and GMC, and two pickup trucks from Chevy and GMC.

The report by GMinsider said that GM has largely shut down plans for hybrid versions of the next-generation GMC and Chevrolet pickups and sport utilities, though a possibility remains that the Cadillac Escalade Hybrid SUV model would remain.

The Escalade had actually sold a larger percentage of hybrids than either of its less-glamorous siblings, though the total numbers of GM large hybrids sold always remained low--from a high of 8,797 across all five models in 2009 to only 3,114 last year.

Work on a revised, smaller, and less expensive version of the Two-Mode Hybrid system had been underway for several years now.

The current iteration of the breathtakingly complex Two-Mode system was rumored to cost GM as much as $10,000 a copy in the low volumes it's sold in. The system produces substantial gains in fuel efficiency, but it has never given the large, thirsty trucks any kind of green tinge.

Instead, several commenters have suggested, GM may be considering boosting fuel efficiency in its full-size trucks by resurrecting the small the 4.5-liter diesel it had fully engineered and then shelved several years ago.

2010 Chevrolet Silverado Hybrid

2010 Chevrolet Silverado Hybrid

Following the GM Insider report, General Motors issued what you might term a non-denial response.

We should stress that carmakers are quite happy to provide information related to future products and their timing when they do want to promote them.

So GM's response indicates the company doesn't really want to discuss this topic publicly at all.

That could mean many things. It could mean that the report is accurate, and that the hybrids are all but dead.

Or it could mean that GM hasn't made the decision yet.

Or that revised versions of the large Two-Mode Hybrid system are still too expensive or complex, or aren't delivering the fuel-efficiency improvements they need to, so they've been sent back to the lab for more work.

It might even mean that the report is flat-out wrong, but that GM will only talk about its future large hybrids when it's good and ready--and not before.

We're a little skeptical that the entire system has been killed off, but we're also skeptical that it could be used solely for a next-generation Cadillac Escalade Hybrid.

Mass production is the key to getting hybrid costs down--3 million Toyota hybrids and counting, anyone?--so restricting a complex, expensive hybrid transmission and battery pack to the lowest-volume variant of GM's highest-volume vehicles makes little sense.

And we'd note one further thing: In the fuel efficiency regulations issued a couple of weeks ago, which will take corporate average fuel efficiency to 54.5 mpg by 2025, there's one provision that might rescue the next-generation Two-Mode Hybrid system.

2009 Cadillac Escalade Hybrid

2009 Cadillac Escalade Hybrid

The rules contain a credit for alternative drivetrains in pickup trucks, defined as hybrid-electric systems--but the credit does not apply to diesel engines.

Many carmakers are not happy about this, including Toyota--which knows a fair bit about hybrid cars--and the German companies with most experience designing and selling diesel passenger cars.

Also, Ford has partnered with Toyota to collaborate on full hybrid systems for large vehicles, including pickup trucks. The partners haven't released any details yet, but we know that work is well underway.

And what Ford does, Chevy usually does too (and vice versa).

So we think there's more to this story than we're seeing right now. Just sayin'.

What do you think? Should GM pursue a smaller, cheaper, more efficient next-generation large hybrid system for big trucks?

Should it replace that direction with small V-8 diesels? Or should it do all of the above to spread its bets?

Leave us your thoughts in the Comments below.


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