At 3,000 miles my glowplugs had a melt down dinging a piston and did a little scoring. The motor would have been fine but it was a new truck, so i wanted a new motor. I got a new long block from gm, and i to make a long story short i got my truck back today. Now it makes a wine noise under boost. Its sounds almost like a cop siren. The gm tec says it is a dinged fin on my turbo. But they said it was alright to drive. I have a feeling it is a vacume or pressure leek on a turbo hose. Also every tubo i have been around that goes out you do not want to drive when you suspect a problem because the usually don't last. What do you guys think.