Four wheel drive only works when truck is cold

1997 GMC C2500
150,000 MILES • 5.7L • V8 • 4WD • MANUAL
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JOE SMITLEY
  • MEMBER
  • 1 POST
When the truck is cold and I first started my four-wheel-drive will engage but as I drive it for a couple miles and or it reaches operating temperature when I engage it to lock the four-wheel-drive in it will not engage. what could be the problem that is only locking in 4-wheel drive when it's cold but it won't lock in once it reaches operating temperature?
Jan 6, 2021 at 5:48 AM
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KASEKENNY
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 18,907 POSTS
Do you know which transfer case you have? Do you have an electronic shift transfer case?

I assume you do so I am attaching the info on this. More then likely the encoder is failing once it warms up.

However, let's just confirm this is the system you have and if not, can you get a picture of your shifter and I am sure we can figure out which one you have.

Let us know and we can go from there. Thanks
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Jan 7, 2021 at 3:37 PM