When it comes to diesel engines, there is only one on the list that depending on who you talk to, might be the best or worst engine out there. Even in a room full of die-hard Ford guys, you're bound to find a good number of them that wouldn't touch the 6.0L with a 10-foot pole but at the same time, you're gonna find some owners who say it's one of the best that they've ever owned. So with all these mixed opinions, is it worth a buy? Today, we'll take a look.
When it comes to 6.0s, we've had a few guys in the shop with them, Dustin had one, Justin had one and Brent had one in an Excursion but you'll see a common theme here. They all had one. They don't anymore. In the 2003 model year, Ford replaced 7.3 Powerstroke for the 6.0 and used it all the way up until '07 in the F-Series trucks and also used it from 2003 to 2005 in the Ford Excursion before the entire platform was killed. with a factory VGT turbocharger, the 6.0 made 325 horsepower and 570-foot pounds of torque which was respectable for the time but not outrageous numbers by any means.
Unfortunately, the 6.0 just isn't known for its power and reliability, it's really more known for all the problems that it had. There were a host of problems that led to total failure on these Powerstrokes but a main source of that was an oil cooler that was inside the block. So engine oil flowed around it while coolant flowed through it but over the time, the coolant side of the oil cooler would get all clogged up with sediment and therefore not cool the engine oil like it was supposed to and at the same time, reduced coolant flow to the EGR cooler.
Another issue the truck was that it used a high-pressure oil pump which also was located in the valley of the engine in the first few years and it was prone to failure because of poor quality materials and the gears that the pump would develop stress cracks and just eventually shatter or chew the teeth right off and boom, you got no oil pressure. So Ford fixed it for 2005 and up-trucks, except this time they had O-ring failures which eventually still led you to not having oil pressure. We've still got more problems to go over.
Both the 7.3 that came before and the 6.7 that came after, use six head bolts per cylinder, but the 6.0 only uses five in this case. Less is not more. With any sort of performance upgrades, more boost and more cylinder pressure, these cylinder head bolts can actually stretch past their torque specs and you guessed it, failed. Failure of these bolts means blown head gaskets or warped or cracked head, yet again, leaving you stuck.
But, what if it's bulletproof?
Well, we're glad you asked. This whole term originated back in June of '09 when a company called The Bulletproof Diesel came up with a solution and replacement parts for these common problems. To be technically bulletproofed, you need to have four of the five main issues resolved. This includes the problematic OEM oil cooler as well as the FICM module, EGR cooler, and water pump at a minimum. The fifth thing is converting your 6.0 from using cylinder head bolts to using stronger head studs. A head stud allows for a higher clamping force than a similar bolt does, thus reducing the chances of a head gasket failure or a stretched bolt. Just keep in mind this whole process, depending on how serious you get can cost anywhere from $6000-$13000 at your local shop but when it's all said and done, you've got a bulletproof diesel engine. Slap on a tune, a little more boost, a little more fuel, and some injectors, and you're easily making 400 to 500 horsepower.