I had a 96 1/2 ton and a 01 3/4 ton Chevy. They both had an electrical solenoid mounted on the top passenger side of the front differential that went bad. This locks in the front axles if it stays locked in the engaged position. In my case, my front diff wouldn't engage, maybe yours does the opposite. Easy to change, costs about $130 at the dealer. Otherwise, you may have a bad switch on the dash if it is electrical.
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Thursday, January 2nd, 2020 AT 9:02 PM