According to unconfirmed reports, General Motors may be planning to revive the shelved 4.5-liter Duramax V-8. The baby Duramax was initially intended for the light-duty Chevrolet Silverado and GMC Sierra but this could also spread to the heavy-duty truck lineup.
Sources told PickupTrucks.com that certain GM officials want to bring to life its plans for the in-house-designed Duramax, designated LMK.
One reason cited was that it is ready to be implemented. GM said that a nicely developed diesel powerplant may give an edge in fleet averages especially when considering that the standards for fuel economy and emissions are in constant scrutiny from state and federal authorities.
GM's truck team said that the 4.5-liter turbo-diesel V-8 was originally meant to be placed in the half-ton, or 1500, truck lineup but it may be used on the three-quarter-ton Silverado and Sierra too. Duramax chief engineer Gary Arvan said that there's still the question on whether it will sell well.
He said that the 4.5-liter Duramax would have "launched [with power ratings] about where the Duramax was in 2001 when it was introduced." The 2001 Chevrolet Silverado 2500 HD with the 6.6-liter Duramax V-8 delivers 300hp and 520 pound-feet of torque.
If we compare these figures to the current LML-series Duramax, which has an output of 397hp and 765 pound-feet of torque, it's easy to conclude how the diesel engine has advanced in nearly ten years.
When it comes to hauling and towing performance, there isn't a lot of difference but the smaller-displacement V-8 could return more miles per gallon, about 25% better than a comparable gasoline engine. GM full-size truck chief engineer Mark Cieslak said that the 4.5-liter V-8 is "fully developed and ready" and could be launched "in a heartbeat."