Over the last couple of days I have done the following: Coolant flush, Egr delete, oil cooler, bano bolts, stc upgrade, blue spring upgrade, upgraded oil tube, ccv mod (just ran hose out to middle of truck for now) and put my 06 turbo back on (had a 03 on) Truck is a 06, It seems to have a humming noise when you accelorate and let off. I don't remeber the turbo sounding like that if its even the turbo. could it be the ccv mod? or maybee a leekly gasket somewhere? or maybee its normal.