4 wheel drive has it's own mind

[capt114]

I have a 2005 Chevy Z71 Tahoe with about 150,000 miles. About a month ago my 4 wheel drive began changing it's selection from 2H to 4hi to 4low to neutral and even sometimes not even lighting up. Every time I start the vehicle, it seems to change. I replaced the switch but it still does it. Any suggestions?

 

[Mako]

I have the exact same car, about 110k and same problem. A friend with a mechanic shop changed the transfer case fluid a few months ago and the problem went away temporarily...but now it is back ? Anyone else know what's going on?

 

[Donut Slayer]

encoder motor

 

[rockenthebowtie]

Or encoder motor sensor for the most part you do need to R/R the encoder motor and open it up to gain access to the sensor and its less expensive than buying the whole encoder motor itself and 95 percent of the time thats all you need only I do recommend that you get it scanned to save your self some money to keep from throwing unnecessary parts at it because it can also be the ATC module which is another common problem