On very cold mornings, 5F or colder, a get a screeching noise from the turbo area. It is not the 2nd air pump starting (although thats there too). It is MUCH louder than that. It sounds like a bad bearing type squeal.
The sound goes away after the motor warms up, or if I rev to about 3k.
Once the car gets warmed up, everything sounds normal.
2 things have recently changed. This is the first time the car has seen these types of temps. I also changed my oil to Rotella 5w40.
Ideas? It will be seeing the dealer in about a week, but they wont beable to replicate it.