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Transfer Case Clicks


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Posted

I have noticed the my truck makes a clicking sound when I turn it off. It sounds like its coming from the transfer case, and it sounds like a quick succession of 2 engaging and disengaging cycles. It all happens within about 3 minutes of turning the engine off and the cycles take place in less than 2 seconds. Is this normal with the autotrac transfer case?

Posted

probably the exhaust, i don't think the transfer case has power with the ignition off..unless you got the occult special edition silverado

Posted

Defintely not the exhaust. Its a mechanical clicking not the clanking and pinging associated the the hot muffler contracting. I just assumed the sound was coming from the T-case, but could it be something with the Evap system? It sounds a little far back to be from the T-case after some investigation. Its coming from the back of the cab around the gas tank area. Ive also been gettin the P0442 code. Thats what leads me to beleive its the Evap maybe. When does it run the test cycle on the Evap system?

 

I dont know alot about these type systems so Im just making assumptions.

Posted

I know the exact sound you are describing and get it every time it turn my Cobalt (2007) off......Haven't noticed it with my truck but my car gives 2 clicks a few seconds after it's shut off, my dad's Cobalt does the same thing. Not sure what it is but it's done it since new. I would say that it's not your t-case and it's normal, should not be anything to worry about.

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