I finally found the real only place is on the ECM, mounted on the drivers side of engine block, there are 2 connectors, it is the forward connector, pin 11 (2nd row from top, 1st wire), which is green and yellow wire, at least it is on the 2005. Search google for ECM connector pinout. I did not connect it, just didn't want to figure out going through from engine compartment to cab. Could not find any info about any available VSS in cab. BTW, I have 05 Ram 2500 crew cab, diesel. Got wiriing diagrams. Will attach pic of that C2 diagram. If you find somplace in cab, please post. Though I did no