Front End Noise when driving 98 Explorer 4.0 XLT

[Bowercw52]

My explorer has 260K+ miles on it, runs great but in the last couple months, I've been hearing a combination groan/whine from the front axle when driving. It winds up and down depending on speed, but gets really loud in the cabin the faster I go. When I drive straight or turn right, it's there. When I turn left (lane changes) - no noise, which should be normal.

All regular maintenance and oil/fluid changes have been done consistently, so I don't believe that's the issue. Also regular alignment and wheel balance/rotate. Tires are all the same Goodyear Wrangler, new in 2014.

I have a 3 position switch on the dash (AWD, 4H, 4L) and the 4H/4L positions seem to work fine as I can hear the clunk and feel the change when I switch back and forth from 4L to 4H, but when I switch to AWD - nothing. Actually, I don't hear a difference in the noise between 4H and AWD, which makes me think it's stuck in 4H. But the noise should be present in all driving, straight, right, or left, correct? Again, the quiet left turning throws me.

If anyone has an idea, please let me know.

 

[XLTrunner]

My recent experience with locked 4WD is that you'll get a distinct chatter or growl on dry surface when making tight radius turns...like into a parking spot or into your driveway...in addition to a growing howling noise as speed increases while driving.

How long since the wheel brgs have been changed?

 

[C420sailor]

Check your wheel bearings. A whirr/growl that goes away during lane changes is indicative of a bearing going south. Jack that ***** up and check the wheel for play.