Are you experiencing repeat failure of the high pressure oil inlet o-ring on your 6.0L injectors? The often-overlooked cause of this problem is the ball tube o-ring in the high pressure oil rail. If close examination of the failed injector seal indicates that it was eroded from the top to the bottom, then the root cause is in the high pressure oil rail. We now have the parts and tools available to correctly do this repair and prevent costly comebacks. Any time the valve covers are removed from a 6.0L engine you should check the oil rails for leaks. This can be done by removing the ICP sensor and pressurizing the system with shop air. You will need to command the IPR valve closed with a scan tool in order to build pressure in the system. Frequently you will find leaks between the ball tube and the oil rail. If there is a leak at one ball tube it is probably wise to replace them all. Even if you do not find any leaks during air testing, it is wise to closely inspect the nipple portion of the ball tube where it inserts into the fuel injector. Even the slightest surface imperfections here are not acceptable. Since pressure in the high pressure oil system can exceed 3,500 PSI even slight surface abnormalities can result in problems over time