Spike45 Report post Posted October 15, 2012 The product was designed by the Cummins Filtration (Fleetguard) Chemical Products group. Before retiring from CF as a field engineer, I worked with the Chem Products group in getting some field testing started. The explanation that there is deposits is accurate. The issue was most notable in High Pressure Common Rail fuel systems that had frequent and repeating injector failures due to the build up of gum deposits that are removed from the fuel system especially since the advent of ultra low sulfur diesel fuel. That fuel is easily capable of removing old gum deposits from every surface it comes in contact with. This would include the pipelines, tank farms, vehicle fuel tank and fuel lines. The importance of the initial treat rate is to provide an intense cleaning of the surfaces within the system. Removal of those deposits has been known to cause filter plugging. It would be a good idea to carry spare fuel filters when doing the initial cleaning. Spike45 Gary Spires Retired Cummins (Fleetguard) Field Service Engineer Share this post Link to post Share on other sites