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2014 Silverado not going into 4wd

darks1d3

By darks1d3
in Engines & Drivetrain

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darks1d3 Enthusiast

darks1d3

Posted
Posted

I have a 2014 Silverado LTZ Z71 that doesn’t seem to want to go into 4wd. I have no “Service 4wd” warning. When I turn the knob to Auto or 4 high the light flashes. I get the messages that it’s going into 4wd. I then hear what sounds like ticking then nothing. The light on the knob goes out and it doesn’t go in to 4wd. Any ideas what I should check first?

davester Senior Enthusiast

davester

Posted
Posted

with the truck in park and still in 4wd mode (at least according to your switch), reach under the truck and try to rotate the front driveshaft.

 

If you can rotate it, then the transfer case (TC) didn't shift into 4wd mode, most likely the encoder mounted on the TC (I think that's the right term) that shifts between the various modes, but could potentially be a problem inside the TC as well.

 

If you can't rotate it, then the TC did shift in 4wd.  Now, lift one of the front wheels off the ground.

 

If you can rotate it, then most likely the actuator on the front diff isn't locking the axle to the diff (so, it's the actuator or an electrical problem to it), but it could be that bits inside the front axle are broken as well (the locking gear and/or the passenger side stub axle also fail).

 

If you can't rotate it, then the truck is in 4wd mode.

darks1d3 Enthusiast

darks1d3

Posted
  • Author
Posted

It's the weirdest thing. The shift from 2WD to 4LO works. 4LO to 4HI/Auto works. 2WD to 4HI/Auto doesn't work.  So it sounds like it could be the encoder? 

  • 2 weeks later...
darks1d3 Enthusiast

darks1d3

Posted
  • Author
Posted

For anyone running into the same issue I took it to the dealership. It was not giving any error codes everything seemed ok. They said they did a "re-learn" or something like that to the computer and that fixed the issue. 

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