Thanks DBC. Not sure. I have had many turbo charged cars (2 Saabs, AWD Celica Turbo, Twin Turbo Z, 1.8t - A4 wagon, Volvo XC). I have never heard a noise like last night. Did not hear it at all today..... Weird!

From your post I get the impression that you think there is a pump that keeps the turbos lubed after the engine is turned off?? No need to let them spool down?