25085515 and 25084374 are the GM parts we used to use to calibrate 88-90 C1500 speedometers. Hope this helps.
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Thanks man I'll try and get this working soon I'll pm you if I have any problems
Any idea if the DBW cruise works the same way by hooking up the DRAC to the speedometer wire like mentioned? I would like cruise in my 93 with 04 5.3L but if not its no big deal..
yes, it will work if you cut the blue/black wire loose from the DRAC and hook the speed output wire from the PCM to it and the Red/white wire, also cut loose from the DRAC.
Any guesses how this would work on a 90 suburban? Im putting a DBC 5.3 in mine. So, would i get my speedo and cruise working by simply doing as the OP said? Or do i need to find the wires that originally fed the speedo in the 90 and somehow tap into those?
never got mine working, it will be easier if you switch to the obs gauges with the needle and tach you could just wire it straight up.
or go with aftermarket ones like i am next month
Ok, so where is the red/white wire? I dont see it on this diagram. Is it from the vortec ecm?
http://i597.photobucket.com/albums/t...vssdiagram.jpg
Also, Does anyone have pics of what they did? or perhaps there own diagram?
You're missing part of the schematic.
I know i did that to make it easier on myself. Heres the rest,
http://s52.photobucket.com/albums/g3...e/9763be87.jpg