At NAIAS 2019, Cummins Inc. unveiled its next generation 6.7L turbo diesel engine featuring a first-in-class 1,000 pound-feet (1,356 N·m) of torque. In addition to an increase in torque, the engine also has a higher horsepower output, taking the 2500 and 3500 heavy-duty RAM pickup truck customers to the next level of performance.
2019 Ram Heavy Duty 6.7-liter I-6 Cummins with 400 hp and 1000 lb-ft of torque
Overall, the new Cummins Turbo Diesel weighs more than 60 lbs. less than the previous-generation engine, yet delivers more power and torque.
The Cummins 6.7L inline-six turbo diesel is offered in two variants; standard output 370 horsepower (850 pound-feet of torque) and high output 400 horsepower (record-setting 1,000 pound-feet of torque).
Base engine improvements made to support the new higher output ratings of the next-generation 6.7L engine include a compacted graphite iron engine block that increases peak cylinder pressure capability; and a new cast-iron cylinder head containing high-temperature capable exhaust valves actuated by all-new hydraulic lash adjusters in the block eliminating the need for valvetrain adjustment service intervals.
The heart of the engine is a higher strength alloy crankshaft with a 10-bolt crank flange driving newly-designed forged connecting rods and new bearings, which transfer power from the low-friction ring wrapped pistons.
A new larger Cummins-Holset variable-geometry turbocharger optimized with heavy duty bearings, and a new compressor-side housing is a key ingredient in the new ratings pumping 33 pounds per square inch (psi) of fresh air into the engine.
The new fuel-delivery system includes a new 29,000 psi (2,000 bar) fuel pump and fuel rail with Cummins Filtration “filter-in-filter” NanoNet technology. NanoNet features many distinct layers of protection to remove and retain particles as small as 4 microns in a composite media structure. These 100% continuous polymeric fibers are bonded together for strength during vibration and flow surges.
Cummins says that NanoNet is 10-13x more effective at removing 4-micron particulate contaminants than the closest competitor, keeping injectors cleaner and optimizing fuel atomization for more efficient combustion.
In addition to displaying the most advanced and reliable RAM 2500 and 3500 heavy-duty engines, Cummins also displayed a 2.8L turbo diesel engine alongside the latest turbocharging, filtration, and light-duty aftertreatment technology.