Turbo Changes Pitch with throttle advance??
05 F350 KR, 6.0 with 130,000mi. My turbo whistle changes pitch when I advance of retard the throttle. It's not a gradual change in pitch, it almost changes in stages if that makes sense.
I've not had this truck for long and it's my first diesel. The turbo whistle has never been particularly clean but lately it almost sounds like one of those little plastic tubes that you spin when we were kids where the faster you spin it the higher pitched the noise.. I don't seem to be losing any boost to speak of and the truck appears to respond just fine (not dogging). I'm also not losing any coolant or experiencing a flutter or "bark"
Searched around in the forums and didn't see anything that quite matched up.. Any suggestions? Thanks guys.