* GM has confirmed it will build a "state-of-the-art" 4.5L V-8 Duramax turbodiesel for light-duty trucks and the Hummer H2 built after '09. The dual-overhead-cam, four-valve V-8 engine will take up about as much space as a small-block V-8 gas engine thanks to integral cylinder-head exhaust manifolds, integral cam-cover intake manifolds, and a narrow block. No output numbers have been released; GM says only that the engine "is expected to deliver class-leading torque, power, and refinement while maintaining a significant fuel efficiency advantage over comparable-output gasoline engines." The General is trumpeting the engine's clean-diesel cred, reporting it will improve engine fuel efficiency by 25 percent, reduce carbon dioxide emissions by 13 percent, and cut particulates and NOx emissions by at least 90 percent.
* In other GM-related news, it has sold its Allison Transmission commercial and military business to private equity firms The Carlyle Group and Onex Corporation for approximately $5.6 billion. GM will retain Allison's Baltimore production facility, which produces transmissions (including the upcoming two-mode hybrid transmission) for GM's retail pickup trucks and SUVs.
* Rumors are popping up again about a Wrangler-sized Hummer H4, to be built for the '09 model year.
* AutoPacific Inc. has released the results of a vehicle satisfaction study, a measure of how satisfied an owner is with his or her new vehicle. In the light-truck area, the Chevy Silverado and Silverado HD, Ford Explorer Sport Trac, GMC Yukon XL, and Toyota 4Runner and FJ Cruiser topped the pickup and SUV classes.
* SEMA reports that the U.S. Senate approved energy legislation in early summer that included a provision to dramatically increase Corporate Average Fuel Economy (CAFE) standards. Passenger cars and light trucks would be required to meet a combined fuel economy average of 35 mpg by 2020. That represents an increase of about 40 percent over the current standard of 27.5 mpg for passenger cars and 21.6 mpg for light trucks and SUVs. Now it's the House of Representatives' turn to produce its version of an energy bill. Stay tuned.
* The BlueRibbon Coalition reports that a "record crowd" of more than 350 off-road recreationists and public land users objected to a federal trail plan that threatens to close 75 percent of OHV routes on forest lands in California's Sierra Nevada mountains. Members of the OHV community spoke up in strong protest to the Forest Service's Draft Environmental Impact Statement (DEIS) for motorized travel management in the Eldorado National Forest, which would close more than 1,000 miles of popular 4x4 roads and dirt-bike trails. Trail enthusiasts stated that many of their favorite routes in the remote backcountry would be closed if the Forest Service follows through with this draft plan. The BlueRibbon Coalition has submitted a formal request for the agency to issue a supplemental EIS to address certain errors in the plan.