4WD grinding sound when engaged

[TheLastBaron]

Hello All, I have previously searched and did not find my specific issue. I have a 2014 Silverado LT about 106k miles. This previous winter I noticed when I put the truck in 4WD there was a grinding noise while driving also a noticeable vibration and dragging feeling while decelerating or accelerating. This is not the "whirring" noise that is common with our 4WD systems, I am familiar with that. I am thinking it is one of the bearings in the front differential, what options are there with regard to trying to isolate which one it is? I was thinking of removing the t-case to diff drive shaft and unplugging the front diff engagement actuator. Then putting it in 4wd to make sure it wasn't the t-case. If that is not it, how can I check the bearings on the input/output for the front diff? Ideas and input appreciated. Thanks.

[asilverblazer]

1 hour ago, TheLastBaron said:

I was thinking of removing the t-case to diff drive shaft and unplugging the front diff engagement actuator. Then putting it in 4wd to make sure it wasn't the t-case.

Doing this would probably upset all the electronics so much it won't shift the transfer case. 

 

Popping the drive shaft out would probably relieve enough drivetrain 'stress' to make some difference.. whether it would help you diagnosis is debatable.

 

I'd check wheel hub bearings first, they are more failure prone than the diff.

[TheLastBaron]

It doesn't really make any noise when the 4wd is not engaged so I assumed that it was not the wheel bearings but something in the front driveline.