Because of the Carpocalypse, GM's announced the 2010 4.5-liter diesel will be put on hold. This is terrible, terrible news because the new Duramax was one of the engines we've been looking forward to for a long time. The new Duramax was and is a design which pokes holes in traditional engine design in ways both fascinating and ingenious. The exhaust gas is directed to the valley of the V8 where the turbo lives, and that turbo breaths into the valve covers, completely eliminating the lower intake, dozens of pounds of turbo piping, and weighty exhaust manifolds, turning diesel engine design on it's ear.
Early testing has the engine as smooth as a gas motor and nearly as quiet while the GM full sized pickups it was installed in returning mileage in the mid to high twenty miles per gallon range. The design may be dusted off later, or it may be sold to whoever may want it, but we're still sad at the lost possibility of a stonkin' diesel in a half ton pickup. [PickupTrucks]