Some folks out there on the ‘Net have reported that GM is planning to develop a new 8.3L Duramax turbodiesel engine for use in its various truck models, citing unnamed insider sources. Looking over the rumors, though, there are a few problems. Here’s why we think the rumors are off-base.
For starters, if GM really was developing a new 8.3L Duramax engine, it wouldn’t go under the hood of The General’s light-duty 1500 truck models. Rather, an engine like that would be better suited for something bigger, like GM’s HD pickups, so the rumors should be evaluated with that in mind.
Right off the bat, though, the bigger-is-better bragging rights mentality of a new 8.3L Duramax engine doesn’t seem to fit GM’s strategy or direction.
“Chasing the highest power and torque figures for the sake of having the highest numbers in the segment doesn’t seem to be GM’s focus in the current T1- and prior K2-generation of its heavy duty trucks,” says GM Authority Executive Editor Alex Luft. “Instead, today’s GM is more focused on delivering the power and torque levels that are useful and balanced for the specific vehicle application, not so much for the purpose of bragging rights. Rather, bragging rights seem to be more Ford’s focus.”
There are deeper issues, as well. For example, even if GM did offer a new monster diesel in its HD pickup trucks, what would it enable the truck to do that it couldn’t do with the current engine lineup?
“The towing and hauling ratings for GM’s current HD models (max 36,000 pounds with a fifth wheel / gooseneck) are not limited by engine output so much as they are by vehicle chassis / platform limitations,” Luft explains. “So, even with more power and torque than the updated L5P currently produces, towing and hauling capacities would not be improved without significant upgrades to other parts of the truck.”
What’s more, at 36,000 pounds, the current setup is hugely capable as it is. Going beyond that would likely be better suited for an entirely different vehicle, such as a Class 7.
“Towing close to the max on any truck doesn’t feel all that great, and to that end, this rumored 8.3L Duramax wouldn’t exactly enhance the experience,” Luft says.
Furthermore, more power and torque can still be achieved without a brand-new 8.3L engine. If GM wanted more more output, the aftermarket has proven that the L5P is capable of far more than the current factory ratings of 470 horsepower and 975 pound-feet of torque, so why not upgrade the L5P, rather than develop a whole new engine?
One possibility is that this rumored 8.3L Duramax could find a home in GM’s MD trucks, but even that seems highly unlikely given the MD lineup’s relatively low volume. Instead, the MD line offers variants of the HD lineup’s powerplants, rather than an entirely unique engine developed specifically for the MD trucks.
“The bottom line is this – an 8.3L Duramax engine doesn’t make sense at all for GM or for its HD trucks, current or next generation,” Luft says.