My 2002 5.9 manual transmission is experiencing bogging and hesitation. The problem started to occur sporadically during moderate acceleration. I have always been faithful to add additive over the years. I changed the fuel filter, but the problem was not solved. I switched to the dirty injector additive and applied a double dose according to instructions. It did pretty good pulling through the AZ mountains from Mesa to Payson to Holbrook....very little hesitation. Just refueled and added cleaning additive again. Now the problem is worse than ever. After startup, it took 7 miles of slow interstate driving before the engine surged and returned to normal acceleration. During that time I could not get the engine to move beyond 1800 - 2000 rpm, regardless of the gear and topped out at 50 mph...no more until the surge of power returned. Afterwards it continued to sporadically lug/surge for shorter periods of time....a few seconds duration. I rechanged the filter right before the symptons worsened. The previous filter, which had just been changed a few weeks earlier was clean. I have no idea what the problem is.....getting ready to head into Indian lands with no services.