Took it into the dealer for service and of course while I am there the shop foreman rode with me and the sound could not be replicated. Went out this morning and of course it is back and pretty consistent. No check engine lights are present more of an annoyance on a brand new truck with 4,600. Anyone else run into this yet and what the remedy is? I only really hear it between 2-3k rpms and it does not seem to go away when the engine warms up.