My 04 superduty 6.0 dsl at around 55-60 started a bogging type condition and blowing black out the tailpipe when i stepped on it. If i stay in it the turbo eventually spools up
and truck takes off. I have been noticeing a whistle whever
i hit the gas but it was not that bad and truck ran ok. A few weeks before i bought 20" crusier chrome alloys with 35x12.50 r 20 toyo m/t hydes for the truck. I had a 3 inch shackle kit put on and trimmed the black trim so no rub. This way the ride stayed fine as opposed to the stagecoach version. Anyway i thought the hydes had thrown off the trucks setup. The turbo appears to spool up at 22-2300 when it used to spool at 17-1800. I remembered reading about people unpluging the egr harness so thats what i did before i left work. Truck seemed to run much better on way home and i could not duplicate issue. I tried 4 or 5 times so i wonder if it,s ok to leave it unplugged. I taped the plug and covered where it plugs in. Ihave about 48 thou on truck but engine and turbo replaced at 37 thou under warranty. Engine is a Fred Jones rebuild with a new or new looking Garrett turbo.