Ford Power Stroke engine
|Manufacturer||Navistar International Corporation|
|Also called||International Truck and Engine Corporation|
The Power Stroke is manufactured by Navistar International Corporation (International Truck and Engine Corporation) for Ford Motor Company. These engines are built in Indianapolis, Indiana and Huntsville, Alabama.
Introduced in mid-1994 under the previous 7.3 Liter Turbo Diesel moniker, it was given the Power Stroke name in 1994. It is a turbodiesel truck engine used in Ford F-Series trucks, the Ford Econoline van, the Ford LCF commercial truck in a 4.5 liter V6 version, and the Ford Excursion SUV.
The first 7.3L was produced from 1988-1993. The original 7.3L diesel was a non-turbo charged indirect injection (IDI) engine, followed shortly after by a turbo charged version. It was very similar to the previous 6.9l IDI diesel engine, which was simply bored out for more torque. This engine was not considered in the powerstroke family. In 1994, the 7.3L went under some changes. The 7.3L was changed to a direct injection (DI) engine from the original IDI engine. Ford also added electronic fuel injectors and gave it the name Power Stroke. This model produced up to 250 hp (190 kW) and 525 lb·ft (712 N·m) of torque. The new 7.3L DI Power stroke had "single shot" HEUI (hydraulic electronic unit injectors) fuel injectors and ran a 15º high pressure oil pump (HPOP) to create fuel injection pressures. The turbine housing was a 1.15 A/R. In 1999, an air to air intercooler was added. The intercooler cooled the charged air from the turbo making it denser. The cooler, denser air would increase the horsepower potential of the engine, while also reducing exhaust gas temperatures (EGTs). The turbine housing was changed to a .84 A/R housing and a wastegate was added. The "single shot" HEUI injectors were upgraded to "split shot" injectors. With larger injectors, the HPOP was advanced to 17º to increase fuel pressures. The 7.3L DI Power Stroke was in production up until 2004 when it was replaced by the 6.0L. The 7.3 IDI and 7.3 Powerstroke are not the same engine at all except manufactured by International for Ford.
The 7.3L (444 CID) Power Stroke was replaced by the 6.0 L (365 CID) for the 2003 model year. This version was built until mid December 2006 (2007 model year). So many 6.0 L Power Stroke engines were proven to be unreliable, and may have cost Ford hundreds of millions of dollars in warranty repairs and leading to a recall and repurchase of at least 500 trucks. The major problem with the Navistar diesel engines is damage resulting from aftermarket modifications to the engine or its operating computer. There were initial quality challenges which Ford and Navistar have rectified. The reliability of the later 6.0L engines, after the dealership technicians were fully trained on the product, has been very good. Some early problems were disastrous, requiring total engine replacement. There were also minor problems resulting from the unreliable variable-vane turbocharger solenoid, EGR valve carbon deposit clogging/sticking, defective Exhaust Pressure (EP) sensor/connector, numerous PCM (Powetrain Control Module) recalibrations, fuel injector harness chafing/crushing and other minor driveability and QC issues. As with competitive engine products offered by GM and Dodge, the 6.0L suffered from an inability to conform to the new Federal diesel emissions standards which took effect on January 1, 2007. There were many running changes to the engine and in the 2006 year model the 6.0 had the lowest rate of warranty claims across the board for Ford Motor Company when compared to all of Ford's gas and diesel engines.
The EGR valve carbon deposit issue in the 6.0L has proved common enough to merit some special attention. When the valve clogs, it requires replacement, which has often been done under the powertrain warranty. However, it is only a matter of time, depending on driving conditions, before the EGR valve will again fail and require replacement. When the valve fails, the "Check Engine" light comes on, and the idle becomes slightly more rough, though the engine continues to function with no apparent loss of power.
There are a number of fixes for this—authorized, and "otherwise"—that will remedy the problem on a longer-term basis. The most permanent of remedies is to modify the exhaust system so that exhaust gas no longer passes through the EGR system at all. This modification can, in some years of the 6.0L, itself trigger a "Check Engine" light, which aftermarket engine programming can remedy. However, while very effective and safe from a technical standpoint when performed properly, this modification is most certainly in the "otherwise" category and can void the engine warranty, due chiefly to the fact that it is illegal in many jurisdictions to bypass the EGR or any other emissions-reduction system except for "off-road" use only.
The engine has an 3.74 in (95 mm) bore and 4.13 in (104.9 mm) stroke for a displacement of 365 cu in (6 L) or 5954 cc. It utilizes a turbocharger and intercooler, producing 325 hp (242 kW) and 570 lb·ft (773 N·m) with an 18:1 compression ratio, with fuel cutoff at 3600 rpm, but having a redline of 4500 rpm only attainable with aftermarket performance programming.
This engine is still being utilized in the E-series until the end of the 2009 calendar year. The engine is the same configuration as the 2007 YM with a diesel particulate filter added to the exhaust system. This configuration would seem to demonstrate that the 6.0L could have been made to meet the newer stringent "2007" diesel emissions standards, if Ford had been given enough time to do so.
A 6.4 L Power Stroke replaced the 6.0L due to new emission regulations for on-highway diesel engines built after January 1, 2007; in early 2007 Ford introduced its redesigned 2008 Super Duty with the new 6.4 liter engine as an option.
The new engine has a 3.86 in (98 mm) bore and 4.13 in (104.9 mm) stroke, resulting in a total calculated displacement of 387 cu in (6.3 L) or (6333 cc). This new engine increased power ratings up 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 serial turbo system. The main components of this system are a smaller fixed vane turbo providing constant boost to a bigger variable geometry turbo. This system is designed to result in almost no turbo "lag" when taking off from a stop. The serial system is set up to provide a better throttle response while in motion to give a power flow not unlike a gasoline engine. The 6.4 liter also has a Diesel Particulate Filter(DPF). The engine computer is also programmed to periodically inject extra fuel (known as "regeneration" in F-Series) to burn off accumulated soot into ash. 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 6.4 has had one recall due to the potential for diesel fuel or oil in the DPF causing a higher than normal exhaust gas temperature(EGT). The recall reflashes the engine computer to derate the fuel in order for the engine to reduce the DPF temperature if an EGT is found to be above Ford's specifications.
There are also recalls for the cooling system, radiators leaking, venturi t and a fuel tank bracket that prevents the fuel tank to slide out when hit from the back.
Slated to replace the 6.4 in the 2011 model year. Output is planned to be 390 hp (291 kW) and 720 lb·ft (976 N·m). This engine will be designed and manufactured by Ford, thus ending its legal problems with Navistar due to the high number of warranty claims on the 6.0 engine.
The Powerstroke engine has been used in the following applications.
Series and Excursion Applications
- Mid-1994–2003 7.3 L
- 2003–2007 6.0 L
- 2008– 6.4 L
- 2011– 6.7 L
E Series Applications
- Mid-1994–2003 7.3 L
- 2004–2009 6.0 L
LCF (Low Cab Forward) Application
- 2005–current 4.5 L