2011 Tundra grinding in 4x4 when turning and 4lo

Hope everyone is well - not posted in a while, Tundra has been clicking right along

but a recent issue has me concerned and stumped on what it could be

Any help or thoughts on what could be causing are greatly appreciated

2011 Tundra Rock Warrior 187k miles , daily 4x4 use to reach home.

when I am in 4x4 high and keep wheels straight I do not experience any abnormal sounds- when I turn the wheels a 1/4 turn or more in either direction, I get a felt in the steering wheel and heard mechanical grinding noise . When I turn back to straight it goes away . In 2x4 there’s no noise, wheel lock to wheel lock both directions

And just the grinding noise - no wheel hop, no impeded wheel roll

4lo I get the same noise immediately upon turning the switch and moving forward. And both straight and turning.

trouble shooting attempts- I lofted front wheels and checked for ease of roll, in all directions . All good in all directions, both 2x4 and 4 high . meaning I physically rolled and turned and rolled the wheels and the noise wasn’t present

So I’m bum fuzzled for sure
Thoughts on what’s causing this?
Blessings and thanks in advance
George
Colorado

 

Is this different than the typical binding that you get from turning in 4x4 on a surface that has decent traction? In 4x4 the front wheels are locked together so one has to have poor enough traction to be able to slip when turning. Otherwise you get mechanical binding as one wheel needs to rotate faster than the other in a turn, but it can't when 4x4 is locked in.

 

Sounds like front diff, or CV axle issues.

 

Yes it’s not the normal binding . I had had hoped it was that

it’s curious that it’s under a load , meaning ground friction - lifted and in 4x4 with me free spinning and turning the front wheels there’s no grinding
But it’s a sound of gear grinding, metal to metal

so I’m thinking front diff as well