What is this wire hanging from my ST 300 tranny?

when in doubt pull the wire lightly. if it comes free its not important do not pull hard whatever you do any stress stop pulling at it. just see how far it stretches and see what clips are there. however i believe its just for a different model but if not get back to me and let me know what you found -RTBBilly

Does your speedo/odometer work, kick down cable work too?

Is it hollow like a vacuum line? If so goes to the engine vacuum system.

@enginecreator: It definitely a wire, I can see the copper in it. Speedo & odometer works. Not sure about the kickdown cable, it does shift. A little hard from 2-1 but after 20 min or so of driving it's smooth. @RTBBilly, I gave it a tug, it doesn't move much. Can't really see where it's coming from. I'll give it another look and let you know what I find!

That wire might be for the variable pitch stator solenoid. I don't think there are any other electrical connections to a ST300. Not sure if the 68's had this feature.

So I followed the wire back to the cluster I'm pointing at behind my brake booster. Thoughts?

I'm assuming it leads to the kickdown on the pedal?

If it is for the solenoid it would go to a throttle switch.

I'll get under it and take a look, thank you!!

Maybe this article will help.

The kick down has a functional wire inside it that works like mechanical brake cable on a motorcycle. So it most likely is the Detent / Variable Pitch Stator Control Solenoid as F_O_R said if its a copper wire.

This article - duh ---- http://www.442.com/oldsfaq/oftsp.htm

I think the ST300 had an electrical down shift.

If it is going into firewall and is hanging down that far it is possible it does not go to trans at all. May also be a good idea to trace it back to where it came from. May go to the engine compartment.

Thanks for all the info! Got under the car and this is the only thing that the wire could've attached to. It was to the left of the governor cover. Wire must have broken off as there's still copper in the hole and it's a bitch to get out. The wire is almost impossible to strip too but I'm working at it.

Yep it does I just looked it up here it is below url; http://www.rockauto.com/en/catalog/oldsmobile,1968,cutlass+supreme,5.7l+350cid+v8,1435875,electrical-switch+&+relay,auto+trans+kickdown+solenoid+switch,4792

Apparently some later transmissions had a wire that helped control the spark advance. I suggest you start by identifying exactly what trans you have - the article gives you all the clues needed.

@enginecreator: it's zip tied to the tranny, goes past the engine into the firewall. Checked under the dash and I can't see any black wires at all.

If its a flat slide in connector in that housing you may can pull it from the flat side with a pair of needle nose out threw it and then slide (housing) on the wire hanging and then you will have the broken off piece out and can solder it together and then slide the housing back down over it.

Let us know how things turn out.

I apologize for the delay in answers, (computer problems). so i took a look at that wire of yours and it looks a lot like that transmission fluid sensor on the back of the transmission driver side go ahead and take a look it should be a brass colored cylinder (or perhaps iron color) i know i'm not greatly helpful but i do try :D -RTBBilly

Thanks for all the help guys, I ended up slowly drilling into the cap with a 9/64 bit and got all the old copper out. The wire was partially melted halfway up (I have zero doubt this is the original wire) so I clipped and stripped that, got it back into the cap. I did put a tiny bit of jb weld on the top of the cap to seal the wire in just as a precaution. Everything's working fine, thanks again!

glad you figured it out :D