I don't have too many data points, I had some whine when it was 25 degrees with the old oil. The whine became more severe at higher rpms, so I ran it a low rpms until the system was fully warmed up, (about a half hour) then the whine wasn't very noticable. After the oil change, I plowed when it was about 30 degrees and I didn't notice much of any whine even when cold. Given the cost, I might have chose to live with the warm-up period if I had it all over to do again.
