522-037 - Oil Rail Ball Tube Repair Kit (Stock Replacement)This complete repair solution allows the replacement of worn or damaged high pressure oil rail ball tubes. This eliminates the need for the costly replacement of the entire oil rail, a common issue on the 6. 0L Power Stroke. The ball tubes supply high pressure oil from the oil rail to the injectors. Worn ball tubes or o rings can leak, resulting in a loss of injection control pressure causing poor engine performance and or a no start or hard start