[JUS10]

when i bought my truck the speedometer cable was unhooked from the tranny. the needle was sitting at.. well, bottom dead center would describe it... i spun the cable before hooking it back up and the needle moved, but then just dropped back down to BDC.. i took the truck out for a drive and low and behold the speedo don't work.. my parts truck speedo also dropped down to bdc after sitting all winter... what's up and how can i fix it???

[ May 11, 2003: Message edited by: JUS10 ]</p>

 

[Kevin45]

Speedometer cable is in backwards!!!

Kevin

 

[JUS10]

honestly?? how did it get put in backwards.. i don't think it was ever unhooked from the speedo..
someone suggested to me that there may be a gear or something missing in the tranny?
i dunno

 

[JUS10]

and don't forget,, my parts truck speedo did it after sitting for a while..

 

[JUS10]

the "clock" spring in the speedo came unwound and bunched up.

 

[Pinto_Guy]

Personally I like the GPS speedos for my project cars/bikes. Autometer makes a nice one and if there is a Marine store around they have them for boats and they work well too.

http://www.rexmar.com/page74.html

http://www.nordskogperformance.net/pdf/GPS_Digital_Instructions.pdf

 

[Stinkin_V8]

At the tranny end of the speedo cable, there should be a sleeve/housing screwed onto the end of the cable. should be about 1" dia. and 1.5" long with a 3/8" hole at the end and an o-ring around it. In the end, there should be a plastic gear, about 1" dia. and 1/2" wide on a plastic shaft that slides into the speedo cable housing. If you're missing the gear, that's likely your problem.

Now, the tricky part is finding the right gear. GM parts desks don't list them corresponding to rear end ratios (they can't, too many other factors) only by number of teeth. So, you could go and buy one in the middle of the range of teeth and try it out. Depending on the speed reported, you'll know if you need more or less teeth. It's a good idea to replace the sleeve/housing at the same time - they wear out too, and can cause failure of the plastic gear.

You may have other problems if your speedo doesn't sit at 0 when you're not driving.