Using stock speedo VSS in place of transfer case output VSS?

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GreaseDog

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Got an 84 C10 that I'm planning on swapping onto a 4x4 chassis, I'll be using a 94 K3500 TBI harness to swap in the 80e. Originally transfer case in the donor had a VSS on the output shaft, this won't work with the stock speedo add it is cable driven. I've read somewhere before that you could use the VSS built into the back of the speedo to feed the PCM the VSS signal it will be looking for. Does anyone know how to go about doing this?
 

kleedus

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it will cause you problems in 4 lo.

not sure how much trouble it will cause but I looked into doing it that way on my 90 crew that I put a 4l80/205 in.

I found a way to put a vss in my 205 tailshaft
 

Jims86

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Pin F8 on the blue PCM plug, grey and black wire goes to the 4wd indicator to alert the PCM what range the transfer case is in. Shouldnt be an issue as long you have it hooked to the indicator, which would be the hot lead to the indicator bulb.
 
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GreaseDog

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If I'm driving the VSS of of the speedo, final speed is final speed no matter if I'm in low gear, low range, or high gear and high range.. Should function just as the original VSS would have since it is on the output of the transfer case.
 

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