The Ford 6.0L Powerstroke engine has a very interesting reputation but I'm not afraid to tell you that most people that go through the motions love this engine. The Ford 6.0L Powerstroke engine has become one of my favorite projects at work. You too will be a proud owner once you are familiar with the engine, how to repair it, and all the common problems and issues surrounding the 6.0L Powerstroke as discussed below.
There's so many places to that I could start to describe this engine, but lets start with an overview. The 6.0L Powerstroke replaced the 7.3L Powerstroke in the middle of model year 2003. The engine has output specs that feature 325 horsepower and 570 foot pounds of torque (compared to max 275 hp and 525 ft.lbs. in late 7.3 manual trans engines). The 6.0L Powerstroke has a noticeably richer power band that gives the truck a huge performance increase and faster acceleration mostly due to the increased control that the variable geometry turbocharger.
Depending on the year of production for this engine, it does vary slightly between the years. The early versions (2003 to early 2004) feature a completely different high pressure delivery system utilizing a quick connect braided hose that attached to a unique to the year oil rail, different intake manifold, an electronic throttle plate on the intake, and an ICP sensor (which is short for Injector Control Pressure sensor) mounted on the high pressure pump housing underneath the turbo. Actually, the ICP sensor was one of biggest problems with this year that we still see constantly at the dealer. Because of its relative closeness to the turbo, excessive temperatures can cause the connector and/or wires to melt. The later models changed it up a bit by relocating the ICP to the front of the passenger side valve cover but the sensor could still fail internally allowing high pressure oil to leak.
Some of the major common issues appearing on both the early and later models of the Ford 6.0L Powerstroke engine include: oil cooler failure, EGR cooler failure, VGT Turbo failure, Fuel Injector Control Module failure, head gasket failure, and common injector failure. Fortunately, most of these major common problems fail in a logical order.
Sometimes a Powerstroke may show symptoms like running rough and smoking white like a freight train. This could be accompanied by trouble code of engine coolant to oil correlation. What has likely happened is that casting sand has clogged up the small passages in the oil cooler causing excessive oil temperature that exceeds coolant temperature by more than 20 degrees. The clogged coolant passage through the oil cooler starve the EGR cooler causing the welds and tubes inside of it to break down and leak. The coolant leak through the EGR cooler allows the coolant an entry point into the exhaust or even intake. The extreme heat burns the coolant and causes the white smoke. Excessive overheating of the engine coolant or oil will cause premature head gasket failure. Head gasket failure can also cause white smoke if the coolant enters into the combustion chamber. Most people like to install EGR delete kits on their truck. They are cheap but only installing that is only fixing a symptom. Again, the cause generally lies with the oil cooler in the first place. Replacement of either the oil cooler or EGR cooler requires the 6.0L Powerstroke Intake Removal.
Those trucks showing a severe lack of power or sluggish boost may have the unison ring inside of the turbo stuck. This situation can cause either a under boost or an over boost situation depending on the load, RPMs, and user command. The best thing you can do for this turbo set up is not let it idle over extended periods of time. Yes, of course that means go out drive it like you stole it sometimes by beating the throttle to the floor and forcing the turbo to make huge sweeping changes a few times a week. Usually an easy fix is to remove and clean your turbocharger but sometimes replacement parts are required. Other over boost situations caused by either mechanical failure or purposeful modification of the PCM through use of a tuner can also lead to head gasket failure. The head gaskets are likely to fail at higher than designed to handle boost situations because of the torque to yield factory head bolts. If you want to release the beast with a tuner, I suggest installing ARP head studs and new head gaskets so it will better handle higher cylinder pressures. To learn more about what is needed to installing head studs and head gaskets, read my article Ford 6.0L Head Stud Installation.
With most trucks being in states where we have noticeable winters, cold hard starting is likely a symptom you will experience. The hard start cold can be caused by several issues such as bad injectors, stiction in the injectors, bad glow plugs, bad glow plug harnesses, failed glow plug control module, or failed or weak FICM - Fuel Injector Control Module. Generally a failed FICM transformer (the piece that steps the voltage up from 12v to 48+v) will cause hard starts. You need a scan tool to easily check FICM output voltage. It can be replaced as a new entire unit or you can install a half shell on all but the 2003 model. Ford no longer sells a half shell, but the circuit board only is available from Dorman. The newer replacement FICM's should run slightly higher than originals and settle out to around 49 volts.