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Transfer Case Shift Motor

sahls01gmc

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sahls01gmc Senior Enthusiast

sahls01gmc

Posted
Posted

My 4wd isn't working, and i'm trying to figure out why. I can hear the motor shift the transfer case from 2wd to 4wd, but I am not sure if it is still working properly.

 

When I engage it into 4wd, it makes a longer sound followed by a quick one. Then when I switch back to 2wd, it makes 1 decently quick sound.

 

Was that at all remotely helpful to you?

 

Please help diagnose some problems if you have any suggestions.

 

 

Thanks

 

 

 

James

poorboy_616 Enthusiast

poorboy_616

Posted
Posted

Mine sorta sounds like a window motor.

 

One quick noise, into or out of 4HI.

 

4Lo it will give me two noises in or out of. Both are quick..... One noise for engaging 4HI, then the second one for dropping into low range and vice Versa.

 

I'll shoot a video here in a bit when I'm not so slammed with my current household plumbing issue....

 

On the newer trucks, there is a heated wax pellet in the axle shift mechanism that expands and locks the "hubs" in. If that's gone bad, than even though the T-case is in 4WD, the front axle fails to engage.......

 

Oh the things I learned when I worked for NAPA!!

sahls01gmc Senior Enthusiast

sahls01gmc

Posted
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Posted

Sweet!

 

Mine is making similar sounds (when I close my eyes and act out both of our interpretations...lol).

 

The sounds are mostly "normal" sounding, except switching out of 4lo if there is slight pressure....then it's more of a clunk.

 

I think I am going to get some electrical parts cleaner and clean all of the connections, to try and rule that out.

 

 

Would I be helping/hurting anything if I were to take the shift motor or the 4WD actuator on the front axle and clean/check them?

 

 

James

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