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auto 4 wheel drive turning itself ON

supermanotorious

Full Member
Joined
Sep 10, 2016
Messages
84
Location
Phoenix, AZ
I've noticed over the last several months on occasion I am in 4WD and I did not request it. So I noticed when I start the truck sometimes, it goes from 2WD to "auto" all by itself. Is anyone familiar with this issue?
 
Many many years ago mine did the same thing while it was still under warranty.

I would notice it was in the wrong setting even indicated it was in neutral sometimes, I took at back to the dealer and they reprogrammed it.

That lasted for a few weeks until it actually dropped from Auto to 4LO by itself while I was driving, I just heard a thump and almost kissed the windshield.

Good thing I was driving slow because there was about 3 inches of snow on the ground. The writeup guy said there was a bad seal on the transfer case encoder motor, but the bill said they replaced the transfer case encoder motor and they replaced the TCCM (Transfer Case Control Module)

 
I'm willing to bet it's just a failed encoder motor. The solenoid eventually wears out, usually due to environmental factors, and the sensor no longer knows what position it's actually in.
 
I will agree with you, but it was still under warranty so they never did tell me for sure what exactly what it was.
Just threw parts at it.
 
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