In a sign of the times, General Motors announced on March 10th that it was suspending the launch of the new 4.5L diesel engine destined for half-ton pickup trucks.

This motor is widely recognized as the most advanced engine General Motors has ever designed. It’s a four-valve, dual-overhead-cam mill and it was specifically designed to fit anywhere a gasoline small-block would fit. The engine has some truly cool and weird features like heads that eliminate intake and exhaust manifolds. The block was to be made of compacted graphite iron.

The hot rod potential of this motor was touted in magazines like Diesel Power and in lots of diesel themed web sites and forums. The motor was supposedly going to carry a 310hp rating out of the box and produce more than 400 ft/lbs of torque.

What we’ve read tells us that the engine would have produced a half-ton truck with mileage in the mid to high 20s. If the project were to be revived tomorrow it would take a year to start seeing these motors roll off an assembly line.