I have a 1995 c2500 6.5 4WD with a 4L80e trans, hard times and troubles.

Started getting mystery codes and the transmission would not shift out of
low.
Finally found the problem, one of the transmission speed sensors was not plugged in and I can't find the connector that goes to it!

It may have gotten ripped off by the terrain here *high up in the mountains on New Mexico, nearest black top 20 miles away.

What I need to know is where the connector came from, the one that is missing is the one that is towards the back. The sensor in the front connects
to the black box under it.

Please help me find where it should be.

Since you say it is a 4X4, then it is a K not a C. The rear output speed sensor is not connected to anything on a 4X4 model. The output speed sensor is located in the output of the transfer case on the 4X4's. Are there any codes present?

Yes the code is 18, however I think it is a false code, the engine runs great.

Is the sensor on the drivers side?0



Thanks


Dan
n

Code 18 deals with the injection pump as that is your cam reference signal. No other codes present? If your speedo works, then your output speed sensor is fine. Your tranny will have 2 sensors on the outside of it drivers side. One is the input up by the bellhousing which is used on your's, and the other is a dummy just there to plug the hole. The output speed sensor is located drivers side in the tailhousing of the transfer case and is a 2 wire plug. There is also a 3 wire plug on the front side of the transfer case for the 4X4 activation switch. The rest of the tranny sensors are internal in the pan.

Thanks everyone!

I live way up in the mountains of New Mexico so lately I have had to become a wrench! My profession is a watchmaker.

I have the sensor coming in tomorrow, will let you all know tomorrow afternoon how it comes out.

Thanks to everyone!

Dan

Well here is how it went,
I replaced the sensor and it worked for 1 day.

Then it went back to its old tricks.

Won't shift out of first.

Could the fact that the power steering hydro lines are leaking.

When it stopped working the power steering pump was running out of
fluid?
Does the fact that the ABS breaks use the speed sensor have and
effect?

Please help, I love this truck and I'm running out of options.

Thanks
Dan

Your at the point now that you have got to get it on a scanner that can read-out what it is seeing. Your simply guessing at it right now without seeing what the PCM is commanding. It could be just about any sensor or even a shift solonoid that is causing your issues. Which sensor did you replace? If it was the one in the transfer case, does the speedometer work now? Did it work before? You could have a failed VSSB, or a bad input speed sensor. Possibly a failed 1-2 shift solonoid, a sticking valve body, engine coolant temp sensor shorted, and so on and so on. There are too many variables to pinpoint this without electrical diagnostics first. Check the 6.5 forum and go under the stickies and see if a member near you has a scan tool.

Thanks, I agree with you. However the closest place to do that is 200 miles away.

I will endeavorer to persevere.

Thanks again
The speed odometer was working before and after.

In so much that I live far away from malls and
car dealers what do you think of this?

http://www.aldlcables.com/sc/details.asp?item=aldlobd1u

I was thinking that I could use this to figure out what the
problem is?

Could I get a clue with this???

Thanks
Dan

FOR OBD1 6.5's, there is no ther option other than GMTDscan tech. His is the ONLY software that can fully access the 6.5's ECM like that of a TECH1 or TECH 2.

http://www.enghmotors.com/tech/order.aspx

Since it worked for a while after you replaced the sensor, I would check the connections real close and also inspect the wiring. If it is severely oil soaked, the integrity of the wire insulation could be sacrificed and could be shorting sensor circuits.
Corrosion at harness end terminals seems to be somewhat common on those also.