I have an 04 6.0 that has 135,000 miles and is still completely stock (motor wise). I am experiencing intermittent turbo issues. I usually experience it when I first get in it to drive, doesn't really matter whether it's overnight, or just been sitting for 15 minutes. The turbo will sometimes not engage until I am going about 30mph, then it will make a chirp/ whistle sound and engage, then it is fine sometimes, but sometimes it will do it again if I stop @ a light. Other times it will not engage @ all for the length of my trip, but I have found if I am going down the road and put it up into neutral and just turn the key off & back on & restart, then the turbo will kick in, like it is an electrical issue with something not engaging it. I took it to a shop & got an oil change and they checked it out and said the truck was needing several program updates which they did, but my problem continued after I picked it up. Help, suggestions, comments????????