Though not officially announced, we already know the answer to one of the biggest questions of the year: GM’s new Duramax L5P 6.6L V-8 Diesel will be rated at 445 horsepower and 910 pound-feet of torque. Though they look good at first glance, how do the numbers stack up when compared to Ford’s Power Stroke and Ram’s Cummins engines?
On paper, the L5P stacks up quite favorably.
|Vehicle||Engine||Horsepower (hp)||Torque (lb-ft)||L5P +/-hp||L5P +/- torque|
|2017 GM Heavy Duty Trucks||6.6L Duramax L5P V-8||445||910||N/A||N/A|
|2017 Ford F-Series Super Duty||6.7L Power Stroke V-8||440||925||+5||-15|
|2017 Ram HD||6.7L Cummins Diesel I-6||385||900||+60||+10|
|2016 GM Heavy Duty Trucks||6.6L Duramax LML V-8||397||765||+48||+145|
GM’s leaked powertrain guide for the 2017 model year denotes that the L5P figures are SAE J1349 certified, which means that the numbers were derived using the latest standards and specifications in engineering.
So, as it stands, GM’s new oil burner has 5 more horsepower yet 10 fewer pound-feet of torque than Ford’s similarly-new 6.7L Power Stroke V-8. When compared to Ram’s 6.7L Cummins inline-six, GM’s new mill makes 60 more horses and 10 more pound-feet of torque. Finally, the new L5P is 48 horsepower and 145 pound-feet more powerful than the LML Duramax it replaces.
With that said, we feel obligated to note that these are all on-paper measurements. As such, real-world performance of vehicles with the aforementioned engines could vary significantly based on a myriad of factors, from the quality of the numbers issued by Ford and Ram, as well as by other vehicle components with which they integrate, such as the strength and durability of the entire powertrain as well as that of the truck frame itself. And the only way to find out about that is to test the trucks in real-world hauling, towing and driving situations. But until that happens, these numbers will have to suffice.