5 ton M929 Transfer case won't shift into low

[dan2002dd]

My transfer case will not shift into low. I have followed the other post on here that say it has an air lock and it should shift with all the air out. It still doesn't, I took the linkage loose to make sure that wasn't the problem and it moves fine when it is disconnected from the transfer case. So that makes me think the air valve is stuck. Has anyone had any experience with this or have any recommendations?

 

[simp5782]

My transfer case will not shift into low. I have followed the other post on here that say it has an air lock and it should shift with all the air out. It still doesn't, I took the linkage loose to make sure that wasn't the problem and it moves fine when it is disconnected from the transfer case. So that makes me think the air valve is stuck. Has anyone had any experience with this or have any recommendations?

Does your truck linkage move free with it disconnected from the transfer case? Or are you saying the in and out sliding bar on the transfer case moves fine and shifts High Neutral Low?

 

[dan2002dd]

The lever and truck linkage moves freely when disconnected. The part in the transfer case does not move.

 

[simp5782]

The lever and truck linkage moves freely when disconnected. The part in the transfer case does not move.

Remove the air supply line from the low range actuator valve right there where the linkage is. The valve that has the roller wheel hitting the washer. See if it will shift with that line removed.

That line will come from the frame rail to the valve. The line will be yellow under the carc.

 

[Tow4]

I had problems shifting the transfer case in my M929 occasionally. I found that if the truck was rolling it would shift easy. With the truck moving, put the transmission in neutral and shift the transfer case.

You can also remove the washer from the transfer case linkage or turn the rod around so the washer doesn't activate the front drive. You can engage the front drive with the switch on the dash when it's needed.

 

[M35A2-AZ]

I think that is a good idea to try.

 

[dan2002dd]

Remove the air supply line from the low range actuator valve right there where the linkage is. The valve that has the roller wheel hitting the washer. See if it will shift with that line removed.

That line will come from the frame rail to the valve. The line will be yellow under the carc.

I have already taken loose the line to the lock cylinder (in the transfer case) but that did not help. I will try this as well, once the rain passes thru.

 

[dan2002dd]

I had problems shifting the transfer case in my M929 occasionally. I found that if the truck was rolling it would shift easy. With the truck moving, put the transmission in neutral and shift the transfer case.

You can also remove the washer from the transfer case linkage or turn the rod around so the washer doesn't activate the front drive. You can engage the front drive with the switch on the dash when it's needed.

I will try this as well. Thanks for the tip.

 

[simp5782]

I have already taken loose the line to the lock cylinder (in the transfer case) but that did not help. I will try this as well, once the rain passes thru.

The cylinder line to the top actuator you can remove that in the chance its holding pressure and not venting. In the other You may have a bent shift fork .

Remove the inspection cover from the top. Unscrew the top actuator from the case and see if the fork will come up and out of the case.

 

[dan2002dd]

Update, I found the shifter interlock cylinder was stuck and would not allow the level to move. The cylinder screws out and when it was removed, I tried the shifter and it worked. I disassembled the cylinder and cleaned up the piston and cylinder walls, they were pretty bad, and now it is working after reinstallation. I found an air leak after finishing so on to the next problem now. Anybody know what the valve that has an air line in it and screws into the water housing on the top passenger side near the front of engine on the truck? It is cylinder shaped and has some holes on the end of it where air is constantly leaking out of one. I forgot to take a picture and I just scanned through the TM and didn't find it.

 

[simp5782]

Update, I found the shifter interlock cylinder was stuck and would not allow the level to move. The cylinder screws out and when it was removed, I tried the shifter and it worked. I disassembled the cylinder and cleaned up the piston and cylinder walls, they were pretty bad, and now it is working after reinstallation. I found an air leak after finishing so on to the next problem now. Anybody know what the valve that has an air line in it and screws into the water housing on the top passenger side near the front of engine on the truck? It is cylinder shaped and has some holes on the end of it where air is constantly leaking out of one. I forgot to take a picture and I just scanned through the TM and didn't find it.

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