We recently toured the Cummins engine plant in Columbus, Ind., where a dedicated assembly line is about to start cranking out all-new 5.0-liter V-8 turbo-diesel engines for the redesigned 2016 Nissan Titan XD pickup truck. And by the looks of things, like this could be a great match.
Depending on the exact version, the engine will produce 315 horsepower plus a healthy 555 pounds-feet of torque. While that number may seem low compared to the 900 pounds-feet of torque produced by the bigger 6.7-liter Cummins found in Ram heavy-duty trucks, this V-8 offers some interesting technology (see video below) like a brand-new two-stage Holset M2 turbocharging system. The system offers Low Pressure and High Pressure modes, which engage at specific rpms and speeds to produce the highest performance possible, all based on demand. The result is a torque band shaped more like a box instead of your average bell curve.
"Ever since we first imagined the engine, we've been working with various OEMs [original equipment manufacturers] to get customer feedback," said Tim Britt, Cummins chief engineer for light-duty engines. "What they all told us they wanted was more fuel efficiency and less pollution — so we began development work on a second diesel truck engine with a cleaner combustion process and lower emissions." Cummins began building the first prototypes for this smaller V-8 turbo-diesel in early 2002.
"Around the same time we moved production of our 15.0-liter commercial truck engine to the Jamestown Engine Plant in Lakewood, New York, to make room at the Columbus plant. Then in 2006 we reached an agreement with a potential buyer to provide our new 5.0-liter V-8 turbo-diesel for their next-generation vehicle," Britt said. "At that point we began preparing the assembly line that still includes part of the original Cummins foundry built in the 1920s, which has part of its original wood ceiling intact."
All 5.0-liter Cummins engines will come from the factory using a 10W-30 non-synthetic motor oil, with 40-weight synthetic recommended for exceptionally cold climates. In Canada and Alaska, Titans also will be equipped with block heaters. Weight was reduced, according to Britt, by building the cylinder block out of compacted graphite iron, which is stronger and lighter than traditional iron. Other lightweight engine components were added, including high-strength aluminum-alloy heads and composite valve covers. The graphite iron block along with the dual overhead camshafts contributes to the engine's improved noise, vibration and harshness characteristics. The new Cummins 5.0-liter V-8 turbo-diesel exhaust system uses a particulate filter, diesel exhaust fluid and selective catalytic reduction that enable the engine to run cleaner. That technology also serves a second purpose — reducing typical diesel noise.
The new engine also features a Bosch high pressure common rail fuel system to deliver precise fuel control with multiple piezo injections per combustion stroke, which helps increase efficiency and further reduces traditional diesel clatter. Finally, the advanced, maintenance-free Bosch ceramic glow plugs provide quick engine starts even in extremely low temperatures, permitting push-button starts within two seconds.
From station one to final inspection, the engine requires just less than eight hours to build and will typically be in Nissan's Canton, Miss., Titan assembly plant within 30 hours of being built.
At startup, the Cummins assembly line will employ 108 people working five-day, 38-hour shifts. We were told Cummins anticipates building at least 13,000 engines for Nissan the first year, but has the potential to crank out up to 100,000 engines with a three-shift workforce. While the engine will be the key feature in the Titan XD, it's also suitable for recreational vehicles, small buses, light delivery vehicles and marine applications. In fact, the first Cummins 5.0-liter V-8s will be heading to Alabama, rather than Mississippi, to be mounted in a new line of Tiffin RVs.
The new Cummins V-8 is also designed to be more fun to drive, with about 45 percent more torque at cruising speed than similarly sized gasoline V-8 engines. And its low-revving power band requires less downshifting, so it will save even more fuel when towing or carrying heavy loads.
"Since the majority of full-size pickup owners only drive a little more than 10,000 miles a year, fuel economy is critical. Titan's XDs are projected to provide 20 percent better fuel economy than a similar-sized gasoline-powered V-8 when towing full loads," Britt said.
Of course, actual fuel economy figures will not be available until closer to the Titan's on-sale date late this year, and if some of the models have a gross vehicle weight rating more than 8,500 pounds, the government does not require Nissan to list fuel economy numbers. Some are hoping Nissan will still submit those trucks for EPA certification regardless of their GVWR.
While journalists were not allowed to drive the prototype Nissan Titan XD on display at the plant tour, the engine was started and given a few revs. Cummins' noise-reduction efforts were clearly evident. Also, there was no detectable odor or visible smoke coming from the exhaust.
As interesting as the Cummins plant tour was, we can only speculate about whether this engine and new truck combination will resonate with buyers. This new strategy of making a "heavy-duty" half-ton with its uniquely reinforced frame, chassis and powertrain (a six-speed heavy-duty Aisin automatic transmission will back up the Cummins) is truly an interesting gamble. But with fuel prices as low as they've been in a long while and the pickup truck segment selling at record levels, the timing for this marriage might be perfect. We'll have more once we get behind the wheel.
Cars.com photos by Peter Hubbard and Mark Williams
Holset Turbocharger
