Ford introduced its 2015 F-Series Super Duty lineup at the State Fair of Texas today.
Key changes include an upgraded second-generation 6.7-litre Power Stroke V-8 turbo diesel engine, as well as increased towing capabilities. There's also a refreshed, top-of-the-line King Ranch model.
Ford is the only heavy-duty pickup truck maker to design and build its own diesel engine and transmission combination, having debuted its 6.7-litre Power Stroke diesel in 2011.
The shorter airflow from the exhaust system to the turbocharger with that unconventional design was said to improve turbo responsiveness and isolate the engine’s highest temperatures, improving performance and efficiency, while also reducing noise, vibration and harshness
Ford's engineers maintained that configuration in the upgraded new Power Stroke. Among its changes, a larger GT37 turbocharger replaces the previous GT32 model, enabling more airflow to the engine, helping increase output beyond the current 400 horsepower and 800 lb-ft of torque.
The wastegate and wastegate controls have been eliminated in the larger turbo, as it operates at lower peak pressures than the GT32. "We’ve dramatically improved performance while reducing overall engine complexity by focusing on the turbo system," explained Power Stroke technical specialist, David Ives.
A further benefit of the larger turbo is improved engine exhaust braking, manually controlled by a push-button switch in the cockpit. Extra engine braking helps reduce wear on wheel brakes and requires less manual brake application from the driver on downhill grades.
Additional changes to the fuel delivery system are said to result in improved combustion, enabling lower noise, vibration and harshness as well as helping reduce the buildup of fuel deposits on valves over extended use.
More accurate fuel control helps improve both durability and driveability – especially when towing.
Other detailed improvements in the engine and Ford's 6R140 TorqShift six-speed transmission are said to provide similar performance to today’s best-in-class fuel economy, even with the improved power output.