• 54

The battle of the diesel-powered half-tons is about to begin, and today General Motors revealed more details on its entrant: the 4.5L Duramax turbo-diesel V8. Thanks to a narrow-angle V block, the 4.5L turbo diesel will fit in the same space as the General's small-block V8, which does give us hope for additional applications beyond just its half-ton trucks. Large SUVs are surely going to get the engine as an option eventually, but maybe GM can find a passenger car or two down the line that would benefit from the tons of torque this engine will produce. GM says the 4.5L turbo-diesel will produce 310 horsepower and 520 pound-feet of torque, while bumping fuel efficiency by 25%. In order to help it meet Bin 5 and LEV 2 emissions standards as well as be 50-state legal, the engine will feature both a diesel particular filter and NOx after-treatment system that uses urea to knock out those pesky nitrogen-based particles. Another engineering coup for the 4.5L turbo-diesel is that GM has reduced its parts count thanks to a design that includes integrated aluminum cylinder head exhaust manifolds and an integral cam cover intake manifold. You'll be able to buy the new diesel in model year 2010 Chevy Silverados and GMC Sierra half-ton pickups, no doubt for a sizable premium over their gas-powered counterparts.

[Source: GM]


  • Scheduled for GM pickup trucks under 8,500 pounds Gross Vehicle Weight
  • Low emissions, high performance and excellent fuel economy
PONTIAC, Mich. - General Motors Corp.'s revolutionary new 4.5L V-8 Duramax turbo-diesel, which makes its debut in Chevrolet Silverado and GMC Sierra light duty trucks in the 2010 model year, is compact, powerful and fuel-efficient. The engine also is lighter, an important consideration in the competitive light truck market, because it was designed with more than 70 fewer parts.

The new dual-overhead cam, four-valve V-8 diesel engine boasts a number of innovative design approaches that have enabled its compact size and mass, including integral aluminum cylinder head exhaust manifolds, integral cam cover intake manifolds and a narrow V-angle block. The new V-8's compact size enables it to fit within the same space of a small-block V-8 gasoline engine and offers GM the flexibility to introduce it in a wide variety of vehicles to meet market demand.

The new 4.5L V-8 diesel is expected to deliver more than 310 horsepower (231 kW) and 520 lb-ft of torque (705 Nm), while delivering a 25-percent engine fuel efficiency improvement versus comparable gasoline engines.

"This premium diesel engine is expected to deliver the power, torque and refinement our customers expect," said Tom Stephens, executive vice president, GM Global Powertrain and Global Quality.

The new V-8 diesel will be GM's first engine to use a selective catalytic reduction (SCR) NOx after-treatment system with a diesel particulate filter to help achieve Tier 2 Bin 5 and LEV 2 emissions, making it compliant in all 50 states. SCR was chosen for its proven NOx reduction capability and durability, and high efficiency while operating in optimal diesel combustion modes, making it a very attractive system to achieve high fuel economy.

The environmental benefits of the new engine include a 13-percent reduction in CO2 emissions and at least a 90-percent reduction in particulates and NOx compared to many diesel vehicles today.

Technical highlights

Robust and innovative, the new 4.5L diesel V-8's technical details include lightweight aluminum cylinder heads with integrated manifolding; a variable-vane turbocharger with intercooling; a compacted graphite iron (CGI) cylinder block for a stronger and lighter base engine (compared to lower-strength aluminum or heavier grey cast iron); and a fracture-split main bearing cap system. GM has applied for patents on a number of these features and expects to have several patents granted before the engine launches.

Compared to typical production diesel engines, GM's new 4.5L V-8 turbo-diesel innovatively reverses the flow of air and exhaust gases entering and exiting the cylinder heads. Air enters the engine through ports in the top portion of each cylinder head. Exhaust gases exit inward between the cylinder heads and directly into a turbocharger.

"By using integral cylinder head exhaust manifolds, integral cam cover intake manifolds and a narrow cylinder block, designers saved space and reduced the engine's weight. And because the engine makes more efficient use of heat, fuel economy and performance are enhanced, and noise and emissions are reduced," said Gary Arvan, chief engineer for the 4.5L V-8 diesel.

An electronically controlled, 29,000-psi (2,000 bar) common-rail fuel system is also used on the engine. It has the ability to inject fuel five times per combustion event, reducing noise and emissions while enhancing fuel economy.

"This new V-8 diesel meets the toughest emissions requirements in North America, and 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 many other diesels on the road today, with noise and vibration performance approaching gasoline V-8 levels."

GM's global diesel offerings

GM (Opel, Saab, Vauxhall and GMDAT) currently offers 16 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 found in the Opel Agila and Corsa, to the 6.6L V-8 Duramax diesel offered in full-size vans, heavy-duty pickups and medium-duty trucks in the United States.

GM introduced the Duramax diesel 6.6L V-8 in North America in the 2001 model year. Since then, customer enthusiasm for it has helped GM's heavy-duty pickup market share jump nearly tenfold in the seven years the Duramax has 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 266,000 people around the world. With global headquarters in Detroit, GM manufactures its cars and trucks in 33 countries. In 2007, nearly 9.4 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.

I'm reporting this comment as:

Reported comments and users are reviewed by Autoblog staff 24 hours a day, seven days a week to determine whether they violate Community Guideline. Accounts are penalized for Community Guidelines violations and serious or repeated violations can lead to account termination.

    • 1 Second Ago
      • 7 Years Ago
      Looks nice, MORE power than the new FORD Diesel
      • 7 Years Ago
      Diesel in a Vette?????
        • 7 Years Ago
        I'd buy one. It would be a lot like owning a classic big block vette; low revs and stump-pulling torque. However, unlike a big block, it would probably get pretty good fuel mileage.
      • 7 Years Ago
      Only 310 hp and 520 ft-lbs from a 'modern' 4.5L turbodiesel? Not a very good state of tune. Those numbers are already being exceeded, in terms of scaled displacement, from BMW and Fiat. They're both pushing 100 hp/liter and a smidge under 150 ft-lbs/liter out of their modern turbodiesels.
        • 7 Years Ago
        Rick, are Fiat and BMW installing their 100hp/liter diesels in trucks?
        Engine tuning for trucks and commercial vehicles is not the same as it is for cars.
        • 7 Years Ago
        Yeah, go to Caterpillar's site. Their engines have well past 10L displacement and make outputs like 500HP. What does Cat have to say about it? They list "conservatively rated engine" as one of their pluses.

        In these heavy duty applications, it's nicer to know your engine can output what it says at a very high duty cycle (i.e. 24/7) without breaking that it is to get more HP.
        • 7 Years Ago
        Always the same stupid remarks. American car companies almost always leaves something in the engine.
        Europeans try to wring everything out of their engines.

        This is not an indication of poor engineering on the domestics part, they're every bit as capable as their european counterparts. It is an indication of opposing engineering philosophies.

        No amount of sniveling on your part will change that philosophy.
          • 7 Years Ago
          Mr. Oak said: This is not an indication of poor engineering on the domestics part, they're every bit as capable as their european counterparts. It is an indication of opposing engineering philosophies.

          Then why not do it if you're capable? Why not bother to show off your engineer's prowess? Why not push the envelope? Why sit there in the shadow of your opponents and be content with so-so results? A good engineer will always strive to push ahead.
        • 7 Years Ago
        Yeah, we leave it to the aftermarket to supply the PCM programmers, the propane injection kits, and etc to bump those figures up nicely, and still make it streetable AND reliable.
        And emissions compliant. :)
        • 7 Years Ago
        An engine for a car or crossover SUV needs to be built differently from a truck engine. A truck engine has to be made to handle more abuse and to last longer. This usually requires that they be somewhat detuned.
        • 7 Years Ago
        Scaling displacement doesn't work very well due to thermodynamic considerations, among others.

        Also consider that more power is easily available on most American truck engines simply by turning up the fuel and air delivery. IIRC, the stock turbo on the 6.6 Duramax will support over 500hp. Detuning like this improves durability when towing the max payload up a steep grade in the American west.
        • 7 Years Ago
        How many cams does this have? That's what I want to know.
        • 7 Years Ago
        I think this engine is partially based on the 6.6 Duramax so that may partially dictate the displacement/configuration. I assuming these are fairly conservatively tuned and are capable of higher power output, but what's the point of dropping it in a 1/2 ton truck if you have to put a 3/4 ton running gear under it to handle the torque?
        • 7 Years Ago
        I'll never get the whole HP/Liter argument.
        If the engine gets comparable fuel efficiency and performance(or in the case of some engines better), who cares?

        I don't get the appeal of high revving high strung vehicles.
        • 7 Years Ago
        You think GM is going to put a stressed to the limit engine in thier trucks and SUVs? They will not. This thing is detuned.
        If it didn't last as long as the rest of the truck (but mabye not the tranny) it would be blasphemous to put it in there in the first place.
      • 7 Years Ago
      Ill take the Ford 4.4 instead
        • 7 Years Ago
        Ford has never built a diesel before, I wish you best of luck.
        • 7 Years Ago
        Payday- since you're not running a fleet (based on getting paychecks from Ford), are you buying a new truck every year? What are you doing wrong?
        • 7 Years Ago
        I have personally owned 7 Powerstrokes, 4 Duramax, and 2 Cummins diesels over the past 14 years...not to mention the 3 VW TDIs and the 2 Mercedes diesels. I can speak from (my limited) experience that the GM and Dodge trucks had better powertrains but the Fords looked better. Don't get me wrong, they are all capable of doing more than they will ever need to do.

        As for being a GM fanboy...Bill Ford Jr. signs my paycheck.
        • 7 Years Ago
        @ C.W.

        Ford makes a great 3/4 ton truck for sure. The engine, however, is average at best and and is one of the areas where it falls behind its competitors. Cummins and Duramax are both great motors but Ford is still wiping egg off of its face from the infamous 6.0L Powerstroke engine. The sooner Ford ditches International the better off they'll be in the long run.
        • 7 Years Ago
        As I quote from a tow truck driver:

        "What, 180,000 miles and it's 1st tow truck ride is because of a master cylinder? This truck has barely 80,000 miles and is on it's 3rd engine."

        It was a late model F350-450(?) with the Powerstroke, carrying our '98 GMC Jimmy when the master cylinder went out last summer.

        Those engines are a joke to the HD diesels.
          • 7 Years Ago
          I doubt it. We have several late model Powerstrokes in our fleet with over 80k miles and all are on their original engines. Granted, most of them are the (best out of the group) 7.3Ls and five are 6.0s (which have performed flawlessly).
        • 7 Years Ago
        I guess when life gives you lemons you make lemonade!

        We're all proud that you would throw yourself on that grenade so that the rest of us can learn from your mistake.
          • 7 Years Ago
          You do realize that the Powerstrokes aren't made by Ford, right?
        • 7 Years Ago
        sorry bud, but RC has a point. it will be a better engine, and more capable engine from a company that makes better trucks. as one-sided as you may be to the General, there is no support to anything contrary to Ford being the absolute top of the Truck game. Their diesels have always been best-in class for towing and even fuel economy (even though all large truck diesel or gas economy is laughable), but the point remains.
      • 7 Years Ago
      I think those are fairly impressive stats. Considering that this smaller engine is putting out as much power as the larger 6.6L Duramax of just a few years ago in addition to having loads more emissions crap applied to it.

      I'm excited to finally see more diesels becoming available. I just wish some of them would be offered in smaller vehicles where they will have the most benefit.

      I just can't wait for our refineries to finally get the hang of refining the ultra-low sulfur stuff so that the prices will drop back down to normal levels. I know it will happen, just hoping it's sooner than later.
      • 7 Years Ago
      Ummmm whats that thingy next to that thingy for?

      • 7 Years Ago
      actually you dont know that yet. no official Ford final specs have been released. we have preliminary info intentionally leaked to the press at the Vegas show and thats it. you think that was by accident? you think they're really tipping their hand entirely already? Ford has a lot of great surprises in store and one of them is another diesel better than Generals.
        • 7 Years Ago
        and you know this how? Oh, yeah Ford doesn't make bad engines. (6.0L Powerstroke?)
      • 7 Years Ago
      integrated aluminum exhaust manifolds? Whoever took the picture left them off.
      These are NOT HD diesels.
      GM is still living the Oldsmobile diesel life.
      • 7 Years Ago
      for those crying bmw engines etc,
      GM never builds screamers, it always builds better power curves than any other automaker, Just drive the new Malibu with V6 or the Corvette or even an ecotec, The Torque curve is such that it will be pulling all the way to the redline in any gear, the redline may come earlier, but, unlike a Toyota or BMW that screams at 6500 RPM and action stopped way back at 3000 RPM, the GM engine will sing its beratone at 6200 RPM, but the action was all the way to that RPM,..
      Just take a cobalt 2.4 Vs. a Scion TC and see what will happen if they race from a rolling start...
      • 7 Years Ago
      Can't wait for Banks to get their hands on this and get rid of all that power-robbing emissions crap.
        • 7 Years Ago

        I'm really disappointed in the urea injection over regenerative modes like on the new full scale d-max.
      • 7 Years Ago
      Diesel applications are the only way full-size trucks and SUV's will survive in the future CAFE standard climate, and this is a great step in that direction.

      HOWEVER, if they continue to charge $6k or more for a diesel... they aren't going to sell. $1500 to $2k? Much more realistic. Take a look at the sales of the VW TDI! They can't keep up with the demand. It's not a case that diesels cannot sell, it's a case that NA automakers don't price them competitively enough and fail to market them properly.
      • 7 Years Ago
      Having been a diesel enthusiast for more than twenty-six years and presently owning seven diesel power vehicles, I no longer see the attraction for the average consumer to own a diesel with the cost of diesel fuel being seventy cents per gallon above the price of gasoline.
        • 7 Years Ago
        The extra cost of fuel isn't the only consideration. There is the extra cost of the engine at vehicle purchase. No matter how you look at it owning a diesel now cost more. I am a devoted diesel fan but I'm not crazy.
        • 7 Years Ago
        $0.70/g is only about 20% more. Most diesels will easily get 20% better mileage than their gas counterparts while giving great road manners with their great torque curve.
        • 7 Years Ago
        Agreed. Hopefully the government will get off their collective asses and get the cost of diesel back down where it belongs. It hurts when I have to fill up my TDI Beetle... or my Powerstroke F250... or my Mercedes 300d.
    • Load More Comments