I have a 2011 3500HD 6.6 and was driving the other day, I got home shut the truck off and when I went back out to run to the store, fired up the truck it started fine backed out fine, through first gear ran great but when I got on the highway to head out. boom. No power to take me past 45 mph and to keep me powering. I took it out on the highway, and I can get it going 75 after awhile of driving but there is no power to get me up the hills. Highest my boost gauge is going is 11 psi. I changed my fuel filter. Still the same thing. I checked the turbo itself and the bearings and everything seem fine. Nothing is loose, and when I fire the truck there is no noise when I press the throttle. The turbo vane doesn't seem to be operating poorly but how can I check or listen to make sure? Any ideas of what I need to check or do before I replace the turbo would be great.