I drive a 2004 Yukon XL and 2 days ago, when making a turn it sounded like something fell out of the front underside of my car. Then made a horrible knocking, churning sound (grinding). When it rained last night, just backing straight out of the driveway it sounded like the front end was about to fall apart! What the heck?? It’s an “all the sudden” kind of thing. Maybe I had heard some mild grinding…thinking it was time to replace my break pads. Pads are still there, btw.
Brakes, Christy? . . . Or Are There Kids On Tricycles In Your Neighborhood?
Check with the neighbors and see if there are one fewer kids than before.
CSA
LOL!!! Good One! 
So, you heard this “horrible knocking, churning sound (grinding)” and you did . . . what?
Did you stop to see what happened?
I doubt this is a brake issue, since it happened while turning. What amazes me is that you’re still driving this vehicle, even though you say it sounds “like the front end was about to fall apart.”
“Maybe I heard some mild grinding.” MILD grinding. I love it. Now that’s an LOL.
Have you, possibly, been driving around with the 4WD engaged?
Just a thought.
LOL
Calm down a bit. I think there is only concern because your post refers to this happening 2 days ago, you’re apparently still driving it, and you could be endangering yourself, your family members, or others by continuing to drive it.
Question. Have you looked at the front wheels closely? Do one or even both appear to be canted in at the top? If so, it sounds like a ball joint is giving up and taking this vehicle even one inch out of the driveway means you need to up the life insurance ante first.
On a 2WD Yukon about all I could see as potential trouble spots would be ball joints, a wheel bearing giving up, or possibly a brake problem. Sometimes the outer pad may still be at least acceptable but the inner may be gone.
Another question. Does this vehicle drive straight or does it wallow or wander?