My parents have an 06 DC Texas Edition that just hit 100k miles. Yesterday it drove fine with no problems or anything, but this morning my mom woke me up calling and saying it made a "scary noise" when she put it in drive, so she reversed back into the driveway and it made a low, grinding noise, so she just pulled back in and parked. When I checked it out it made a loud whining noise in park, almost like a vacuum. It went away after a minute-minute thirty, and all gauges were fine. The research I've found online says it's some sort of bearing or fan clutch blah blah. OR it's "completely normal." But i know it isn't because now the Check Engine Light is on. I'm pretty crafty with tools and a gearhead myself, but I'm a Jeep man. So any ideas or advice before I rip through the engine bay or take it to a shop?

Thanks,
Justus

What are the CEL codes? That will be your best clue as to what's wrong.