GM Repair Problems? Ask GM Repair Expert Now.
It sounds like you have a slipping transfer case encoder motor. Do you plan to diagnose/fix it yourself?
I would try disconnecting the transfer case control module and then drive the vehicle. If it stops happening then the control module is likely the problem- it is putting the transfer case in neutral by it's self. If it doesn't stop then I would replace the transfer case encoder motor- it is worn and allowing it self to slip in into neutral.
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