Filed under: SUVs, Trucks/Pickups, Green, Chevrolet, GM, GMC, HUMMER
GM announces new 4.5L V8 Duramax diesel for half-ton trucks and HUMMER H2

Mark your calendars, because we're calling today a watershed moment for the advancement of diesel's acceptance in the U.S. General Motors has just announced a new 4.5L V8 Duramax turbo-diesel powerplant it plans to use in the Chevy Silverado and GMC Sierra half-ton pickups, as well as the HUMMER H2. The new oil burner is expected to produce at least 310 horsepower and 520 ft-lbs. of torque. It features dual-overhead cams, four valves per cylinder, a variable-vane turbocharger and aluminum cylinder heads with integrated manifolding that helps keep the overall package small enough to fit in the same space as the automaker's small-block gas V8s.
That's right, just imagine the possibilities. Wherever GM uses a small-block V8 gas engine, it could potentially use the 4.5L V8 Duramax diesel. In a few years we could be driving diesel Impalas, diesel Camaros, maybe even a diesel Corvette! To quote GM's press release, the engine's small size gives it "the flexibility to introduce this engine in a wide variety of vehicle applications should there be future market demand." Indeed.
GM estimates that the engine will improve fuel efficiency by 25%, reduce CO2 emissions by 13% and decrease particulate and NOx emissions by at least 90% in its GMT900 pickups and the HUMMER H2. Whoever said the HUMMER H2 was on its way out will likely be proven incorrect after this engine debuts. Scheduled to be built at the GM Tonawanda engine plant outside Buffalo, NY, the 4.5L V8 Duramax diesel will be 50-state emissions compliant and meet 2010 diesel emissions standards, as well. GM claims its new diesel will also have NVH (Noise, Vibration and Harshness) levels approaching those of today's current gas V8s, though we'll have to wait and see if that wish comes true. That wait should end in a couple of years, as the automaker states the engine will be available in Silverado, Sierra and H2 models built after 2009.
UPDATE: Pickuptruck.com's Mike Levine has learned from GM that despite sharing its name with the older 6.6L Duramax diesel that was developed in partnership with Isuzu, the new 4.5L Duramax was developed completely in-house by GM.
Check out GM's full press release after the jump for more details.
[Source: GM]
PRESS RELEASE:
GM Plans First Light Duty V-8 Clean Diesel For North America
- High-efficiency V-8 scheduled for pickup trucks under 8,600 pounds Gross Vehicle Weight and HUMMER H2
- Low emissions, high performance and excellent fuel economy
- Expected to deliver class-leading torque, power and refinement
- Manufactured at the GM Powertrain Tonawanda engine plant
The premium V-8 diesel is expected to deliver class-leading torque, power and refinement while maintaining a significant fuel efficiency advantage over comparable-output gasoline engines.
The new dual-overhead cam, four-valve V-8 diesel engine will fit within the same space of a small-block V-8 gasoline engine. This compact size is made possible by using integral cylinder head exhaust manifolds, integral cam cover intake manifolds and a narrow block.
"This new GM light duty diesel is expected to become a favorite among customers who require excellent towing ability and fuel efficiency," said Tom Stephens, group vice president, GM Global Powertrain and Quality. "It will meet the stringent 2010 emissions standards, and it will be compliant in all 50 states, making it one of the cleanest diesel vehicles ever produced."
Environmental benefits of the new engine include a 13-percent reduction in CO2 versus gasoline engines, and at least a 90-percent reduction in particulates and NOx compared to diesel vehicles today. This will be GM's first engine to use a selective catalytic reduction NOx aftertreatment system with a diesel particulate filter to help achieve the Tier 2 Bin 5 and LEV 2 emissions standards.
Technical highlights of the engine include aluminum cylinder heads with integrated manifolding; a variable-vane turbocharger with intercooling; a Compacted Graphite Iron (CGI) block for a stronger and lighter engine base (compared to lower-strength aluminum or heavier grey cast iron); and fracture-split main bearing caps and connecting rods for a precise fit. An electronically controlled, ultra-high-pressure, common-rail fuel system is used, which has the ability to inject fuel five times per combustion event to control noise and emissions.
"This new V-8 is not only a clean diesel meeting the toughest emissions requirements in North America, it also delivers an effortless performance feel because of its high torque across the speed range," said Charlie Freese, executive director of GM Powertrain Diesel Engineering. "It is also significantly quieter than other diesels on the road today, with noise and vibration performance approaching gasoline V-8 levels."
Freese said the new V-8's compact size enables it to fit in the envelope of a gasoline small-block engine, which provides GM the flexibility to introduce this engine in a wide variety of vehicle applications should there be future market demand.
The premium V-8 diesel engine is expected to deliver class-leading refinement, horsepower and torque and fulfill multiple vehicle applications with ratings in excess of 310 horsepower and 520 lb-ft of torque.
GM (Opel, Saab, Vauxhall and GMDAT ) currently offers 17 diesel engine variants in 45 vehicle lines around the world. GM sells more than one million diesel engines annually, with products that offer a range of choices from the 1.3L four-cylinder diesel engine sold in the Opel Agila and Corsa, up to the 6.6L V-8 Duramax diesel sold in full-size vans, heavy duty pickups and medium duty trucks in the U.S.
GM first introduced the Duramax diesel 6.6L V-8 in the U.S. in the 2001 model year and since then, customer enthusiasm for this heavy duty diesel has been outstanding. In fact, GM's heavy duty pickup truck market share has jumped nearly tenfold in the six years that Duramax engines have been offered.
General Motors Corp. (NYSE: GM), the world's largest automaker, has been the annual global industry sales leader for 76 years. Founded in 1908, GM today employs about 280,000 people around the world. With global headquarters in Detroit, GM manufactures its cars and trucks in 33 countries. In 2006, nearly 9.1 million GM cars and trucks were sold globally under the following brands: Buick, Cadillac, Chevrolet, GMC, GM Daewoo, Holden, HUMMER, Opel, Pontiac, Saab, Saturn and Vauxhall. GM's OnStar subsidiary is the industry leader in vehicle safety, security and information services. More information on GM can be found at www.gm.com.
Reader Comments (Page 1 of 5)
bmoredlj 3:53PM (6/15/2007)
Me likes....
*grummgrummgrummgrummgrummgrumm*
Reply
Naysayer 3:58PM (6/15/2007)
"In a few years we could be driving diesel Impalas, diesel Camaros, maybe even a diesel Corvette!"
No, we won't.
Reply
The Other Bob 4:04PM (6/15/2007)
I have to agree. I doubt this will make a good car engine.
I would like to see even smaller engines, like a little 4-cylinder diesel for the H-3 and Colorado.
Torqued 4:00PM (6/15/2007)
A fuel-efficient H2? I'll have to find a new reason to hate them...
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MikeW 9:23AM (6/16/2007)
Crappy headlights.
zeos 4:03PM (6/15/2007)
i have always been a ford truck fanboy, but if i have to choose between half ton chevy a diesel and a half ton ford with a wiener 4.6 or gas gussling 5.4; i'll go chevy every time.
also how come dodge never put the 4bt into their half ton trucks, it seems that dodge would have made a lot of money that way.
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Greek Boy 2:30PM (6/16/2007)
Ford will have their 4.5L Diesel offering soon as well.
It is a modified version of a popular 3.6L Diesel in Europe.
In addition to the F-150, it should find its way into the Exepedition too.
Ryan 1:46PM (6/16/2007)
I concur. I missed an opportunity years ago to replace the 2.3L gas burner in a Ford Courier with the Mazda diesel. I would kill to have 30(+) MPG city/hwy in a small truck. I don't need the capacity to tow a house, but I do have need for a REAL utility vehicle with respectable MPG. Until then, I'll sit on my 4-cylinder Accord that's paid for and make do.
Don 4:07PM (6/15/2007)
25% increase in fuel efficiency?
So, if the 6.0L Silverado averaged 12 mpg in a recent C&D test...that means the diesel would raise that figure to about 15 mpg.
Pardon me if I'm not jumping for joy.
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Atlanta Andy 6:01PM (6/15/2007)
You made my point before I got to the keyboard.
Brian 7:23PM (6/15/2007)
Don, are you trying to look stupid? the 6.0L is not the correct engine to compare to, it's the 5.3L which currently gets 16-20MPG in a 4x4 1500. Add 25% to that and you get 20-25MPG. On top of that a truck that pulls a heck of a lot better than a 5.3L gas powered version....you should be jumping for joy!
Don 6:15PM (6/15/2007)
Hey, don't get me wrong...any increase in fuel efficiency is great. But I was expecting better than that...say, maybe a hike up to 18 mpg? Possibly better?
Jeff 6:48PM (6/15/2007)
It might not sound like much, but if it's driven 12000 miles a year, that means 800 gallons of fuel instead of 1000.
To save that much in an Accord, you'd have to go from 30 mpg to 60 mpg.
To save that much in a 60 mpg Prius, you'd have to park it and walk everywhere.
Don 6:53PM (6/15/2007)
Well...when you put it that way it makes me look stupid. ;)
Don 7:34PM (6/15/2007)
Easy there, Brian...no need for insults.
Steve 8:34PM (6/15/2007)
Well first of all they are not comparing the efficiency of the 6.6 liter duramax with that of the new 4.5 liter diesel engine.
The way the press release is worded the 4.5 liter diesel is being compared to the current engines in the Silverado/Colorado line. I would assume they are talking about the 5.3 liter v8 which gets around 16-20 mpg.
So if the 25% increase is applied to the 5.3 liter engine the diesel might get closer to 20-25.
If that were the case I would definitely considering the purchase of a Silverado.
Bruno 12:35AM (6/16/2007)
I'm guessing C&D test them at full throttle much of the time, and use brand new trucks not yet broken in, reducing their real world numbers. And if you need a truck, what else besides a diesel is going to do any better? I am curious what a diesel light duty would get in terms of mileage.
Eric 12:03PM (6/17/2007)
That is so wrong, in the GM and Chevy 1500's right now there is a 5.3L V8 and it gets from the Chevy website 2wd 22mpg so with the 4.5L it will or should get 27.5 mpg they dont use the 6.0L as a standered engine thats only in the max or 1500HD do your research before you comment next time!
Don 12:27PM (6/18/2007)
Didn't realize I was studying for the bar exam, Eric...how 'bout laying off the coffee?
4thPine 9:23AM (8/24/2007)
This should get pretty good mpg, I know some one with a chevy 2500 with the 6.6L duramax and they get 21 mpg without pulling anything and 9 mpg pulling a 12,000 lb trailer.