Originally Posted by Garaphin
Thanks both for the follow ups.
So the noise it makes isn't alarming or anything... and I think that 747 analogy is pretty good. Just sounds like unecessarily loud revving as I approach 2nd gear from first then suddenly it sounds just fine. I should mention to that it really only occurs first startup in the morning, after it's sat for a day or two. It's not a daily driver for me and later startups in the day don't really have this issue.
Also, no Check Engine lights, no error codes when I do the key trick. Thanks also for the tranny filter explanation. I had a mental picture of the 4.0's filter in my head and realized just last night that the 4.7 has a two part filter system.
Before you start it, open the hood and if possible have someone else start it while you see if a ton of air is being blown by the cooling fan. You can even hold the idle up by hand at the throttle body. If the noise goes away, as well as the air flow slows down, I would figure on a new fan clutch.
When you do this, please stay away from the fan and anything else moving under there. Just not sure how familier you are with underhood stuff, sometimes people just do not realize how dangerous it can be.