The 6.0 Powerstroke engine that we work on a lot at 441 Diesel. It is probably one of the most notorious diesel engines ever built due to it’s high number of parts failures and the high cost of engine repairs. What we have found from working on them for 10 years is that the 6.0 base engine (block and pistons) is actually a very strong foundation and can last 500k+ miles like its predecessor the 7.3l. The initial problems the 6.0 had were a combination of injector failures, EGR cooler failures, and head gasket failures. The lack of knowledge on the engine and diagnostic methods caused these issues to take excessive amounts of time to repair and also caused repeat failures shortly after. The fuel injectors in the 6.0 have a tendency to heat up at the nozzle and this can cause the nozzle to stick and allow combustion into the fuel system causing the fuel to be pushed out of the cylinder head. Many times the engine would act as if it was running out of fuel and the most common diagnosis would be a bad fuel pump. After checking fuel pressure techs would find excessive pressure and bubbles in the fuel system. After removing glow plugs one at a time the problem cylinder would be isolated and the injector replaced. This was a sizeable learning curve since this issue did not exist with the 7.3l. Below is a pic of bubbles in the fuel system from a bad injector.
Next we will look at EGR cooler failures. To start we should cover exactly what an EGR cooler is. To make the federal mandated emissions for 2003 International added an EGR cooler to the 6.0 Powerstroke. This EGR cooler uses engine coolant to cool a stream of exhaust gas from the engine in order to make the exhaust cool enough to recirculate through the engine when the EGR valve opens. This allows the engine to essentially recycle some of it’s exhaust and cut down on emissions.
When this system is operating correctly it does just as advertised and allows for a cleaner burning engine. When it fails however it can cause much destruction. When the EGR cooler fails it will push coolant out of the exhaust through the turbo and out the tailpipe. In extreme cases, it will pump coolant into the intake locking the engine down and blowing the head gaskets. In the 6.4l Powerstroke this will may times caused a bent connecting rod.
These pictures are off a 2005 6.0 Powerstroke. The pic on the left is the turbo followed by the exhaust manifold and then a view with the cylinder head off. This engine had blown head gaskets from the extreme pressure caused by coolant seeping in on top of the piston while the engine was running.
There are several options to remedy a bad EGR cooler.
- Aftermarket EGR cooler (Bulletproof) This will maintain your emissions and also provide you with a lifetime warranty against further failures.
- Factory EGR cooler replacement. This is simply replacing the cooler and since Ford has never overhauled their design will cause further failures down the road unless the oil cooler temperatures are monitored closely and a partially clogged oil cooler replaced immediately. Even then a repeat failure can still occur. ]
- EGR delete. EGR delete kits remove the EGR cooler and valve and reroute coolant back in to the engine. This is the only way to ensure no further failures but this method is for off-road use only and is ILLEGAL for on-highway use.
This brings us to the head gasket failures that plague the 6.0 Powerstroke. This issue is the most widely known failure and is the single issue that gives the 6.0 Powerstroke a bad name. We keep records of all repairs at 441 Diesel and after going through our records I can confidently say that we have found that most (75%) of the head gasket repairs we have done on this engine are related to 2 issues.
1. Programming – If you think that Ford left any room for more hp in their engine with the hard parts installed you are mistaken. The big 3 auto manufacturers are in a constant battle to have the most horsepower. What that means is that if they could’ve put 450 hp in the 6.0 they would have. Most programmers have the capability to add upwards of 120 hp to the 6.0. This means that the 230 hp that International built the engine to withstand is essentially expected to withstand double the power. If you want to add power to your 6.0 plan on installing ARP studs and o-ringed heads. It’s the only way to make it last.
2. Bad EGR cooler – In the pictures above you can see the amount of coolant an EGR cooler can pump into the intake. The piston of the engine is already pushing a lot of pressure through the exhaust valve ports so if you add a liquid to the mix you can expect a gasket failure.
I will say that the Ford head bolt design is inferior to every other engine out there and I’m not giving them a pass I’m just making the point that only 1/4 of our head gasket repairs are on stock engines with good EGR coolers. The 6.0 only has 10 big head bolts and they are torque-to-yield so they are known to stretch under extreme load. With that being said we have 10+ International trucks that we service and we have had 0 head gasket failures on these engines because they are 215-230 hp and they are maintained meticulously.
I’ve got blown head gaskets! What next?
441 Diesel has the fix that lasts. We use ARP studs, Ford head gaskets, and o-ringed cylinder heads to ensure that you never have to worry about your head gaskets again. ARP studs are made for racing and are much stronger than the factory bolts preventing stretching. Ford head gaskets are the best out there right now and if you get a quote from anyone using black onyx gaskets please RUN. Our machine shop will rebuild your heads to factory specs and then install o-rings that will bite into the head gasket ensuring a permanent seal that gives you further protection at extreme boost levels. We also replace your oil cooler, clean your turbo vanes, and reseal your high pressure oil pump (upgrade STC fitting if applicable).
This is a shot of a set of rebuilt heads before installation. You can see the steel O-rings cut into the head.
If you have a 6.0 and want a quote on our head gasket repair or want to ask any questions don’t hesitate to call. Thanks for taking the time to read. AJ