Hi all, I have a 2005 F350 KR with the 6.0 PS (163K), 3 days ago I noticed, what sounded like a turbo wine noise after driving a couple miles in the morning (-15 F), if I slowed down the noise would go away and if I sped up, it would go away, then it just went away and didn't come back the rest of the day. It did the same thing the next day, but yesterday it didn't do it. Yesterday at the end of the day, I checked the coolant and there is this clear wax looking stuff in it, not a lot, but there is enough to hang onto the sides of the reservoir. I did notice a tiny bit of this substance in the reservoir last year and just cleaned it out with a rag and it didn't come back. Truck starts and runs fine, I don't have to add coolant....not sure if the two are related, I only look at the reservoir to make sure it is not low, normally, this time I took the cap off and looked inside.....sound familiar to anyone? Thanks in advance!