Oil drip from Front Axle Switch M939-A2 / 927-A2 Transfer Case Problem SOLVED

[99nouns]

Yes
The yellow data plate behind the steering wheel also states the same thing. Shifting must be done at speeds less than 20 mph.

Now that raises another question for me, while moving trans in N, forget about getting the tcase shifting, I cant even put it in N, I was able to do that once or twice and when I got to the point when it was shifting Lo it started grinding noise, I even pressed gas pedal and than I heard grinding lost frequency and when the gears were aligned it shifted. So there seems like there is something else other than the lock rod mentioned in the first post is preventing tcase to shift...

Simp also confirmed none of his trucks ever shift on the fly nor moving...

If I come to full stop, I still have to jiggle that tcase shifter to get it, some times I even have to throw trans in 5th and N just to get gears turn alittle so it would shift, definitely some thing is off...

Any ideas?

 

[Ford Mechanic]

I normally try to soft mine with it rolling a little. Shifts alot easier that way. If I do it sitting still I normally can't go completely into the other gear. I have to then bump the shifter into drive and back out quickly and it will grind and pop into gear.

Sent from my SM-G900V using Tapatalk

 

[99nouns]

What swamp donkey has posted in operating manual, it says there is an another safety system called lock up solenoid that prevents tcase to switching gears unless the trans is in N, which mean s that solenoid can be defective or not receiving signal from the transmission, and that definatley is not the air cylinder solenoid on the tcase, because that only operates from the switch on tcase handle on the floor, so there must be another one lockup solenoid somewhere else? Perhaps in the transmission. Am I miss understanding it?

 

[Swamp Donkey]

What swamp donkey has posted in operating manual, it says there is an another safety system called lock up solenoid that prevents tcase to switching gears unless the trans is in N, which mean s that solenoid can be defective or not receiving signal from the transmission, and that definatley is not the air cylinder solenoid on the tcase, because that only operates from the switch on tcase handle on the floor, so there must be another one lockup solenoid somewhere else? Perhaps in the transmission. Am I miss understanding it?

When the button on the shifter is pushed it activates the shift lock solenoid, which pulls in the shift lock cylinder. This let's the shifter move up and down. This solenoid is on top of the transfer case.

When the button is pushed, the 5th gear lock up solenoid is also activated. This is done to ease shifting. This solenoid is mounted to the driverside of the transmission.

TRANSMISSION 5TH-GEAR LOCKUP SOLENOID VALVE - Activated by transmission control switch and transfer case switch, the 5th-gear lockup solenoid valve directs main oil pressure of transmission to the transmission governor system. This puts transmission in 5th-gear, creating less drag on transfer case synchronizer which permits smoother shifting from one transfer case drive range to another.

 

[99nouns]

Thank you for that info let me see if I can find where that is and trouble shoot it... If it is activated by the button on the shifter than it must be electronicly wired...

 

[99nouns]

I have found the TRANSMISSION 5TH-GEAR LOCKUP SOLENOID VALVE it was in a tight place behind that plate.




I placed my hand on it and pressed the button on the tcase lever and it did click, I dont know if that means it is working or not, could it be just clicking but not opening?

 

[simp5782]

I have found the TRANSMISSION 5TH-GEAR LOCKUP SOLENOID VALVE it was in a tight place behind that plate.


View attachment 640568

I placed my hand on it and pressed the button on the tcase lever and it did click, I dont know if that means it is working or not, could it be just clicking but not opening?

Cut the ground wire behind that plate off and relocate it. There are two pig tails. One to the truck one to group. Its probably a bad ground. I relocated mine when I did my shifter cable.

Sent from my SM-G860P using Tapatalk

 

[99nouns]

Cut the ground wire behind that plate off and relocate it. There are two pig tails. One to the truck one to group. Its probably a bad ground. I relocated mine when I did my shifter cable.

Sent from my SM-G860P using Tapatalk

Simp you did it again thank you, you were right about the ground...



The capacitor is grounded on transmission as well as the solenoid and I dont know if the ground was bad or the Transorb Diode was bad but now I am able to successfully shift from Lo to Hi on tcase while moving, but I get a high frequency whining sound when I shift from Hi to Lo and gears wont mesh...
I have the front axle engagement washer on the lever moved back so it only actuates from the dash switch not automatically when Lo range is selected on tcase, do you think that might be the reason why my gears wont mesh?

 

[TedCat]

Following, just diving into similar tcase nonshift issues.

 

[99nouns]

I never got the t-case to shift smooth at higher speed than just rolling a bit. But what ever the question may rise please post it.

 

[gstirling]

this is a great post, having just replaced my interlock cylinder this post was a great help, but one minor correction: as stated air pressure keeps the interlock cylinder pushing with sufficient force on the pin/rod to prevent shifting while in gear. the correction is - when air is let off (transmission shift to neutral), the spring does not push the cylinder up, but actually still keeps a small amount of pressure down on the pin/rod. the spring is on the top of the cylinder and pushes down the same direction as the air but with much less force. I suspect to keep the pin/rod riding on the shaft but soft enough to allow a shift Hi-LO. thanks for a great post and even better pics.

 

[ladoublet]

Sure is good info - Thanks to simp again