M936A2 transmission lines found disconnected

[dcowan]

This truck is new to me so I have been going over things and found some disconnected steel lines and a disconnected wire on the transmission. Wonder if anyone can help me identify these and why they might be disconnected.

Here are some pictures of the steel line



And here is a picture of the electric wire that is disconnected

 

[simp5782]

That is for the 5th gear solenoid to put the transmission in 5th gear when you depress the button on the transfer case linkage for easier shifting on the fly. That diode goes to the wire spider on top of the transmission that is bolted to the bottom of the cab.

None of it is needed unless you are planning on shifting while moving. Then you would need it. Normal allisons do not have it on it. It is simply for the transfer case.


Do you have issues shifting your transfer case when the truck is running with normal air pressure while sitting still?

 

[dcowan]

My main problem I am fighting right now is a below 1000 rpm wanting to die and idle issue that is detailed in another thread and I am slowly getting better with some work and fuel system fixes/replacements. I have a hard time getting into reverse or forward without killing it or getting it rolling first, but I believe this is more a fuel issue than transmission issue just based on how it behaves in neutral.

I do have issues shifting the transfer case with the truck running in neutral with engine running at full pressure. Sometimes it works fine. Sometimes not. I have verified that the air selenoid clicks with the engine off and hitting the transfer case button so the button and wiring seem to be ok there.

Can you explain the wire a bit more. You say it goes to the spider on the top of the transmission and a diode. What is its function?

 

[simp5782]

My main problem I am fighting right now is a below 1000 rpm wanting to die and idle issue that is detailed in another thread and I am slowly getting better with some work and fuel system fixes/replacements. I have a hard time getting into reverse or forward without killing it or getting it rolling first, but I believe this is more a fuel issue than transmission issue just based on how it behaves in neutral.

I do have issues shifting the transfer case with the truck running in neutral with engine running at full pressure. Sometimes it works fine. Sometimes not. I have verified that the air selenoid clicks with the engine off and hitting the transfer case button so the button and wiring seem to be ok there.

Can you explain the wire a bit more. You say it goes to the spider on the top of the transmission and a diode. What is its function?

I energizes the solenoid for 5th gear and the transfer case solenoid on top at the same time when the transfer case handle button is pushed.

Delete the transfer case interlock solenoid all together. Especially on a wrecker that you will be using that shifter a good bit. You simply need a 3/8 to 3/8 pushlok union. To connect two lines together

https://youtu.be/N7--6jxGDBM

You have a fuel issue.