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Hal, Chevy Master Tech
Category: Chevy
Satisfied Customers: 1031
Experience:  ASE and Chevy Master , 31yr Dealership exp,
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2008 chevy silverado 2500 hd: duramax..four wheel drive is coming on

Resolved Question:

I have a 2008 chevy silverado 2500HD with the duramax and alision in it. My service four wheel drive is coming on. I do not have any four whell drive. the turn button used to indacate wherther it was in 2 wheel 4wheel high or four wheel low the light dose not show any thing in.
Submitted: 6 years ago.
Category: Chevy
Expert:  Hal replied 6 years ago.

Hi my name is Hal.

You need a scan tool that is capable of reading all power train codes not just engine codes. There is a trouble code stored in the TCCM ( transfer case control module)

If the service 4 wd message displays.

The code will tell exactly what is going on, and needed to make a diagnosis. Power train warranty on this vehicle is 5 yr 100,000 miles.

It will deal with the components that shift the transfer case, switch, TCCM module, shift actuator .

I recommend taking to the dealer to be diagnosed, for this repair is likely to still be covered under power train warranty. Check with dealer for covered components.


If you need more information PLEASE ASK a follow up question.

Thank you Hal.

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