I've got a 88 GMC Sierra that originally had a mechanical speedometer. A newer 700r transmission was put in and it has a electric speedometer fitting on the tail of the trans. The truck currently has no speedometer and I would like to put one in, say, a Autometer or Equus. The problem is the wires are missing that would go from the tail of the trans to the speedometer. Where can I get the wiring to run from the trans to the speedometer? Thanks.

 

Should have had a electronic speedo originally...I had a 88 and I figured out via the shop manual set I have how to calibrate it(the cluster). If you want a mechanical speedo then take the tailshaft off and tap the reluctor ring off of the output shaft. Then you'll need the gear and housing. Try www.bowtieoverdrives.com for some 700R4 parts. For an electronic speedo I think BTOD can help you there too. Good luck.

Dave