Funny you should say that your '05 4.4 doesn't sound the same.... I just took mine in because the engine now has a little bit of a whine that follows RPM - similar to a supercharger sound or bad pulley.

When I had my dealer keep it for a day they said the usual: "Could not replicate in shop or on test drive." Baloney! I called the shop foreman out to the parking lot when I picked it up and asked him to listen. He right-away heard it and was completely perplexed. He said it sounded like a leak at an intake valve... Hmmmm.....

They kept is all day today and, with the help of the regional engineer who was visiting this shop, could not diagnose the problem. Meanwhile, I'm tooling around rather handily in a 545 loaner.