The 2016 Nissan Titan XD's 5.0 Cummins diesel V8 is designed for longevity and low-noise output. But the M² "two-stage" two-turbo setup is where that beastly 555 lb-ft of torque figure, and theoretically robust powerband, come from. Here's how it works.
The engine runs a compacted graphite block, steel crankshaft, and aluminum alloy heads, all intended to keep weight down, run quietly, and last a long time.
With the M² turbo setup, that engine should theoretically be boosted to make good power from low speed all the way up to cruising velocity. The basic concept is pretty simple; a small turbo gets spun up at low engine speeds and a big one kicks in when RPMs rise.
The M² also uses tech Cummins calls Rotary Turbine Control (RTC) to channel the exhaust gas which spins the turbos as needed. It moves between High Pressure Two-Stage Turbo Mode (short burst of big power), Low Pressure Single Stage Turbo Mode (more power during speed transitions), Wastegate Mode (regulating pressure in the turbo for maximum efficiency) and Regen Mode (sets engine up for better emissions performance when possible).
Cummins promises that this order of operations will give drivers "more responsive and efficient power control, [and] create a seamless driving experience."
Diesel fuel is delivered to the engine by a Bosch High Pressure Common Rail system, also supposedly improved for this year to improve economy and reduce pollution.
The 2016 Nissan Titan XD is supposed to make 310 horsepower and 555 lb-ft of torque in a fairly flat curve, but we haven't seen one on a dyno yet.