Here's the story- while I was stationed in South Korea this past year, my wife was operating our '05 Durango (120K mi) on a daily basis (back in the USA...). During this time, the engine developed a slight knock and a rough idle, frequently stalling when stopped. Since I was half a world away, I told her to take it into the dealer mech to be looked at. While they didn't give her a specific problem, they offered to change the engine out... sounded fishy to me, so I asked her to get a second opinion. Street corner mech referred by a friend suggested it might be a stuck valve, to do a few oil changes to see what happens... over the course of 2 changes, the knocking and rough idle went away, but now that I'm back, I'm stuck with an intermittent whistling while accelerating. I still have a little ticking in the engine, but nothing that resembles a knock. I did a search on this forum for whistling noises, but the few that came up were related to after market throttle body spacers, which I don't have... the engine is performing well (no bogging down, rough idle, great gas mileage on the highway) so I'm stumped on the noise... any help on this would be greatly appreciated! Thank you!!