M936 PTO problem

[engineer233]

I recently got my M936 home and can't seem to get the rear PTO to engage. I have read the TM's related. The other thing which I think is related is the transfer case will not pull in low. I have adjusted the linkages and it pulls to where it should engage but the truck will not pull. I have drained the fluid and refilled. The fluid was nasty looking and a tad brassy looking in the sun. The one other is I know I'm low on hydraulic fluid but the PTO should still engage shouldn't it ?? I need all the advice I can get. Thanks......

 

[guns1977]

With the truck off, open the right rear air hookup and drain air pressure off. then you should be able to shift the transfer case. the rear pto on the left rear of the seat try with the transfer case in netural put the trans in drive and put your foot on the break like you are stopping then it should allow you to shift the rear pto for the bed in gear the handle should be all the way to the back of the cab. hope this helps

 

[1 Patriot-of-many]

My transfer case simply will not shift unless there is less than 60lbs of air in the tanks. With trans in neutral, hand brake set I just pump the brakes to dump the pressure then shift transfer case to neutral. Then pull the PTO lever back. Mine generally won't engage until I then put the trans in 1-5 then push the PTO lever all the way back, you'll feel it engage. Then run the engine up to about 1400 rpm. You should be set. TM's say the PTO fluid level needs to be in the proper range or damage can occur.

 

[M35A2-AZ]

On my M936 I have to move the transfer case lever up and down a little to find just the right spot to get the pto to go in.
I think the wrecker transfer cases have been used a lot and have a lot of slop in them.

 

[engineer233]

I got to the bottom of one issue tonight. I took the pto off of the transfer case and quickly found the problem. The internal shifter fork had came loose . The set screw for it had backed out and let it fall out of place.. There was also the gear that goes onto the output shaft on the transfer case was loose and the set screw for it was also gone.. Hopefully in the morning I will get some new screws and loctite and get it back together for a test. The bearings in the pto don't feel the best ever but will work for the short term. My transfer case still on the other hand still seems to have an issue, but I will deal with that tomorrow ..

 

[Hawssie]

I dont mean to change the subject but since this problem seems to be solved I have a strange (to me at least) situation regarding my rear PTO on my wrecker(M936A2). I have no problem engaging everything, but when I first get it going and I set the rpms around 1400, then start working the boom everything works but it is pretty slow. Then after I don't know 3-5 minutes there is a louder noise from the hydraulic system then everything speeds up at least twice as fast. In other words its like the hydraulic flow is slow at first then maybe warms up? Where I am is not cold (California) no even below 60 degrees outside. I havent starting diagnosing anything yet. I just havent seen this with any of my numerous other hydraulic stuff.

 

[DKnoll]

My "new" M936 transfer PTO has never worked since I brought it home from GL. Now it's in the shop and we found the PTO pump gears are stripped, so all the internal gears were dry and the bearings shot. I'm having a hard time finding a replacement PTO. So, here's the question: is there a off the shelf or civilian equivalent to this part ? I found the Timkin bearings, I think, but not the PTO pump. (From the looks of the gears laid out on the table, I probably should replace the whole PTO.) Thanks for your consideration.

 

[Csm Davis]

My "new" M936 transfer PTO has never worked since I brought it home from GL. Now it's in the shop and we found the PTO pump gears are stripped, so all the internal gears were dry and the bearings shot. I'm having a hard time finding a replacement PTO. So, here's the question: is there a off the shelf or civilian equivalent to this part ? I found the Timkin bearings, I think, but not the PTO pump. (From the looks of the gears laid out on the table, I probably should replace the whole PTO.) Thanks for your consideration.

May have extra pto to sell will count them up. Guys if you have to dump the air to get your TC in and out your lockout is not working the button switch is bad or the actual lockout on the TC has a problem. As for the changing rpm check you air ram you are probably loosing air pressure and that's how long it takes to go down.

 

[engineer233]

Member bbf may still have some as well.

 

[funky winkerbean]

Was wondering if you got your question answered. I am having the same problem with my 936. I think the transmission is upshifting into a higher gear and its supposed to be in first? Any help would be appreciated.

 

[m16ty]

Was wondering if you got your question answered. I am having the same problem with my 936. I think the transmission is upshifting into a higher gear and its supposed to be in first? Any help would be appreciated.

There were 3 different people with 3 different problems posted on this thread. Which one are you referring to?

 

[funky winkerbean]

I was referring to the trans on my 936 upshifting when im in rear pto. It always worked perfectly then one day it started overspeeding the hydralics. I checked pressure on trans at 5th speed solenoid out port and i have 190 psi. Not sure what the fluid is supposed to control in trans and if I am on the right track. Any help will be appreciated.