Ford Power Stroke Bulletproofing Tactics

Head Problems
When Bulletproof Diesel started our project, they warned us about the likelihood of cracked valve seats on the heads of our donor rig's engine. If ever there were a time and place to pull the heads and check for this, it was then.

Our donor truck had just over 40,000 miles on it when we arrived at Bulletproof Diesel. Despite being completely unmodified, many of the valve seats of the cast-iron heads had developed cracks. While these heads offer great flow characteristics, thanks to having four valves per cylinder, the lack of hardened valve seats makes them prone to premature failure. The porous iron material that was used for the OE heads isn't capable of withstanding the high heat and pressure developed during the combustion process. The result is the formation of small cracks where the valve contacts the machined seat surface. Bulletproof had our donor's heads Magnafluxed to check for cracking. Magnafluxing is a process whereby an electromagnetic field is applied to the material, in this case the cast-iron heads. Once the magnetic field is applied, a small amount of colored metallic dust is spread over the magnetized area. When the metallic dust meets the surface, it reveals cracks immediately, thanks to interruptions in the magnetic field. This inspection method allows very small cracks to be visible to the naked eye.

After installing ARP head studs.

Head Studs
Like most engines manufactured today, the stock 6.0L utilizes head bolts that are designed to twist and stretch to a specific torque value to do their job. This means that as torque is applied to the head of the bolt, the shank or body of the bolt must twist as the bolt stretches to create clamping force. According to Ford, the 6.0L head bolts should be tightened to 85 ft-lb of torque. Head studs do not twist; instead, they use threaded nuts to stretch the stud and create clamping force. Due to the nature of the design, head studs can provide much greater torque values over standard head bolts. Greater torque helps ensure that the head gaskets remain sealed when cylinder pressure and combustion temperatures spike. The published torque spec for a set of ARP head studs for the 6.0L is 210 ft-lb-more than twice that of OE head bolts.

OE Oil Filter Issues
The Ford 6.0L uses a cartridge-style oil filter element that is located on top of the engine.

Here you can see the Bulletproof Diesel air-to-oil cooler unit after it was installed in our donor truck. The included mounting bracket spaces the factory air-conditioning condenser away from the core support, leaving just enough space for the new cooler to mount between the intercooler and the condenser.

Here you can see the Bulletproof Diesel air-to-oil cooler unit after it was installed in o

To access the element, a black plastic cap is turned counterclockwise. As this cap unscrews, the element inside releases a spring-loaded drain valve that allows oil in the filter housing to drain back to the oil pan. One common problem related to this setup involves people trying to perform oil filter changes themselves. Many Power Stroke owners don't realize the importance of oil filter maintenance. Rather than twisting the filter from the housing as is common in a number of OE applications, the 6.0L unit must be pulled straight upwards. Twisting this element can cause big issues for the lubrication system. The filter element has the felt gasket

How It Worked
The improvements Bulletproof Diesel made to our donor F-350 required extensive man-hours to complete. All said and done, our bill totaled $ 7,500 for parts and labor (not including the Be Cool and Amsoil products). But when you stop and consider that this truck is used primarily for hauling expensive construction equipment to and from the jobsite, the expense is easily justifiable. The people at Bulletproof Diesel know their stuff, and with their product solutions installed, this Super Duty's owner has a new restored sense of confidence in his vehicle.

We don't recommend attempting this type of project without a vehicle lift. The process of removing and reinstalling the cab to the chassis requires extensive knowledge of several critical vehicle systems-not something you want to attempt at home with floor jacks. However, the upgrades are straightforward once you have access to all sides of the engine. As with any project of such depth, we expected a few days of driving would shake out anything that may have been overlooked. Much to our surprise, after nearly 5,500 miles of service, the owner of our donor Super Duty reported no major problems associated with the vehicle. The engine oil temperature is no longer tied to the temperature of the radiator coolant, and because of this, the engine runs cooler on long grades and while pulling trailers. Now that we have resolved all the common issues associated with our 6.0L-powered donor rig, we plan to follow up with a selection of power and efficiency upgrades as part of a towing special in next month's issue. Stay tuned.