2008-2010 6.4L

The 6.4L Power Stroke was introduced for the 2008 model year. Strict emissions regulations and the overall questionable reliability of the 6.0L were the primary factors that presented a need for a new clean slate engine. Quieter and cleaner than its predecessors, the 6.4L Power Stroke was the first engine introduced to the light truck market that utilized dual turbochargers from the factory. This was the first Power Stroke to use a diesel particulate filter (DPF) in order to nearly eliminate particulate emissions (soot). The new DPS and active regeneration system greatly hindered the engine's fuel economy capability, though the engine proved to be comparatively strong and reliable. The engine was ultimately retired after the 2010 model year, as Ford replaced the engine with its own in-house built 6.7L Power Stroke for 2011 and on.

The engine has a 3.86 in (98 mm) bore and 4.13 in (105 mm) stroke, resulting in a total calculated displacement of 387 cu in (6.3 L) or (6333 cc). Despite having to meet emission regulations, the new engine was able to increase horsepower and torque ratings to 350 hp (261 kW) and torque to 650 lb ft (881 N m) at the flywheel. Horsepower and torque are achieved at 3,000 rpm and 2,000 rpm respectively. It also features a compound VGT turbo system. Air enters the low-pressure turbo (the smaller of the two) and is fed into the high-pressure turbo (the larger of the two), then directed into the engine or intercooler. This system is designed to result in reduced turbo "lag" when accelerating from a stop. The series-turbo system is set up to provide a better throttle response while in motion to give a power flow more like a Naturally aspirated engine. The 6.4 liter also has a Diesel Particulate Filter (DPF) and dual EGR coolers which are capable of reducing exhaust gas temps by up to 1000 degrees before they reach the EGR valve and mix with the intake charge. The Diesel Particulate Filter traps soot and particulates from the exhaust and virtually eliminates the black smoke that most diesel engines expel upon acceleration. The engine computer is programmed to periodically inject extra fuel in the exhaust stroke of the engine (known as a "regeneration" in F-Series) to burn off soot that accumulates in the DPF. This engine must run on Ultra Low Sulfur Diesel (ULSD) fuel which has no more than 15 ppm sulfur content; using regular diesel fuel will result in emission equipment malfunctions and violate manufacturer warranties.

The 6.4L has had one recall (Safety product recall 07S49 was released on March 23, 2007) that addresses the potential for flames to come from the tailpipe of the truck. This problem arises from the DPF which is part of the diesel after-treatment system. A PCM recalibration has been released to eliminate the possibility of excessive exhaust temperatures combined with certain rare conditions resulting from what is becoming known as a "Thermal Event".

Key Specifications:
• Fuel Injection System: High Pressure Commonrail
• Valve Train: OHV 4-valve
• Compound VGT Turbo
• Diesel particulate filter
• Advanced multi-shot Piezoelectric fuel injection control version. The cylinder block has also been updated using CGI material to increase strength and reduce weight.