M923 Transmission Assistance Please!

[quickfarms]

Check to make sure the selector shaft is moving through all of the gears

 

[Doomsday]

Check to make sure the selector shaft is moving through all of the gears

Do you recommend doing this by removing the pan or watching the cable move it down from the outside...?.....I have checked its operation from the outside and it seems to be functioning properly but without the pan removed I can't say the same for the lever actuating the valve body components on the inside.....

 

[FP1201]

The Neutral safety switch has two wires: power in and in the N position power out. That's not what I'm referring to; look on the other side for a device with a fluid line going in and out. I'm thinking it was something to do with the PTO buy just don't remember. I'll ask around the Shop today for opinions and memory corrections.

 

[FP1201]

The lever is only a piece of flat stock with a couple flats cut in the hole where its nutted to the shaft going inside; it's possible that nut came looks and stripped/damaged the flat-stock lever, hence the suggestion to remove the cable connection and manually move it; if it's loose/worn you'll feel excessive movement before it "clicks" into gear.

 

[FP1201]

The other thing that just occured to me; Is the Parking Brake FULLY released? Nothing blocking the lever? That transmission has more power in reverse than in forward gears (remember the thing about NOT putting the transmission in Reverse with the transfer case in Low Range)

 

[FP1201]

The electrically controlled valve on the side is for the Torque Converter lock-up; That's sort of the "extra gear" you feel if you're counting shifts.

 

[Doomsday]

Parking brake is completely disengaged when I am attempting to put into gear, made sure of that numerous times in initial investigation. I wi go ahead and remove nut n flat stock tonite and see what I find. I am pretty certain there is nothing like the device you described on the passenger side of the transmission but I will look again......only device I was thinking of that you described was that governor valve on the driver side in the top of the first picture I posted.

 

[FP1201]

Parking brake is completely disengaged when I am attempting to put into gear, made sure of that numerous times in initial investigation. I wi go ahead and remove nut n flat stock tonite and see what I find. I am pretty certain there is nothing like the device you described on the passenger side of the transmission but I will look again......only device I was thinking of that you described was that governor valve on the driver side in the top of the first picture I posted.

The device under the shift cable with a line in and another out is the fluid valve for the converter lock-up (didn't see it the first time I looked at the pictures) the little switch by the lever is the neutral safety. I suppose it's possibe the shaft broke inside with enough material left on it to move into reverse. (even a broken crankshaft in an engine will continue to run). the lever & nut look undisturbed, so it's not likely the problem, but always check the easy stuff first. (IF for some reason you pull that shaft, it comes out from the inside, be sure to de-burr the outside before trying to pull it through.

 

[o1951]

As I said in post 26, I think you should do what you said in post 16. At this point, it looks like a hydraulic issue.

 

[Doomsday]

Ok, well got the fluid drained and the pan off. Pulled the spin on fliter as well. The spin on filter up by the cooler had little bit of sparkly's in its fluid I poured out of it but nothing alarming I would say. The pan fluid had about 5 small, small pieces of metal from something, each like the size of a knat to be specific..... light amount of typical black sludge on the bottom and also a little sparkly fluid but nothing alarming I would say, probably from typical wear. Didn't see anything wrong inside from a good visual inspection. Moved the shift selector shaft through the positions and it seems to be operating fine. Replaced the pan filter too since I was in there.....just gonna put pan back on, fresh fluid and hope for the best. I will report back with results soon......

 

[Doomsday]

Well, shoot, that didn't work, back to drawing board.....

 

[Doomsday]

Removed the transmission myself last weekend and got it down to Dartco in Anaheim only for them to tell me the clutches are toast and it needs a full rebuild......for the whopping total of $2600! Ouch! Wish I knew this before I bought the truck as the guy I got it from obviously abused it by not maintaining it at all. I remember when I changed the coolant (well I should say water as that is all that was in it, yeah water and it was black as night) and flushed the entire cooling system, the trans heat exchanger was plugged pretty good on the inlet side with tons of sediment and rust shingles. So clearly the trans was not getting properly cooled at all and it overheated and destroyed the friction plates in the trans. So now, not only do I not have the money for the rebuild, I either need to just save $ or find a good reliable used unit.

 

[Xanadu]

I have a 1986 m923 runs great all works. Trans will not shift to 4&5th gear. No slip, nothing burnt, down shifts and high and low work the same. Is there a governor on the trans? This is a Air Force five ton. Please help I’ve tried everything

 

[simp5782]

I have a 1986 m923 runs great all works. Trans will not shift to 4&5th gear. No slip, nothing burnt, down shifts and high and low work the same. Is there a governor on the trans? This is a Air Force five ton. Please help I’ve tried everything