The Hummer-Replacing Oshkosh JLTV Will Run A GM Duramax Diesel V8

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The Oshkosh Corporation was just awarded a huge contract by the U.S. military to build the truck that will replace the Hummer, dubbed Joint Light Tactical Vehicle (JLTV). Now we’ve heard JLTV will be powered by Duramax diesel V8 engine and an Allison transmission, just like a Chevy truck.

Oshkosh’s VP of Business Development Operations Jennifer Christiansen told Automotive Newsseveral engines” were evaluated before they landed on GM’s 6.6-liter offering. Though I have a feeling it might have had something to do with the fact that many of military’s existing Hummers, Humvees, HMMWVs (or whatever you want to call them) already run GM diesel engines and so a lot of support infrastructure could be carried over.


But any way you slice it, this is a pretty solid engine. Technically the product of DMax; a joint venture between GM and Isuzu, over 1.5 million of the things are already in service in all kinds of pickup trucks and vans around the world. Here in America they see duty in the HD Chevy Silverado and GMC Sierra pickups (plus a few bitchin’ vans), and are rated for 397 horsepower at 3,000 RPM and 765 lb-ft of torque at just 1,600 RPM. Roar!

The Duramax 6.6 is a four-valve high pressure common rail direct injection diesel. Civilian versions are equipped with a diesel particulate filter to meet current stringent emissions requirements, but I bet that will come off for the military. These engines are capable of well over 1,000 lb-ft of torque once you start playing with ‘em, especially if you don’t mind making a little extra soot.


GM’s been tightlipped on whether or not the military-spec version will be uprated, but we’ll stay on it and keep you posted.


Images via Oshkosh Corporation, GM

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