M50D popping out of fifth

[IAmTodd]

There are several types of metal that are not attracted to a magnet, and large, important parts of your transmission, like the aluminum case and brass shift synchros are made of some of those metals.

Thanks, I understand brass and aluminium are not magnetic. However the shift bushing theory makes sense since they're darker colored and the previous upper shift bushing that I removed was black.

Good call though. I tried to repress that thought as I don't want to have to remove the whole lump again. Once was good enough for me.

 

[tx3nc]

I may be onto something. I was playing with the slider and the notched wheel(? I'm sorry if I'm not using the correct terms) that fits inside it. I noticed that toothed wheel has an offset. Is it possible mine was installed backwards? Mind you this trans has been open once before.

This side was against fifth:

This was against reverse:

What leads me to think this is there are two areas worn where picture 1 sits against reverse. Not sure if that's normal or not. Just grabbing at straws here.

Any help is greatly appreciated.

How easily does the slider move back and forth on the mainshaft?

 

[IAmTodd]

Not sure I follow your question. The shift fork moves the hub on the counter shaft. Nothing on the main shaft moves.

 

[tx3nc]

Not sure I follow your question. The shift fork moves the hub on the counter shaft. Nothing on the main shaft moves.

I'm sorry, you are correct. The hub is on the counter shaft not the main shaft. What I'm getting at is how easily does that inner hub move on the shaft. That sliding hub assembly is what engages the gear and if the transmission is 'popping out of gear' it's because that hub is disengaging from the gear. That could be because the hub is not freely sliding on the shaft, the teeth on the outer ring of the sliding hub could be worn, the shifter fork could be worn, or there could be a problem in the shift linkage in the top cover.

You are correct that the hub is directional as to how it should be installed on the counter shaft. I will try to remember to look at my service manual when I get home and let you know which direction is correct.

 

[IAmTodd]

I read on another post there should be a dot on the hub and that should face the rear. I'm going to check that when I get home. The ring moves on the hub smoothly. I don't believe the hub moves as it's sandwiched between the two gears. The teeth look to be in good shape. That was the first thing I checked as the disengagement is quite harsh. The shift fork fits snuggly around the ring and does not appear to be bent. the fork slides on it's rod smoothly as well. I popped the ball and spring out and they're both in good condition.

This is the thread I'm referencing. It sounds exactly like my issue:

http://therangerstation.com/forums/showthread.php?t=17784&highlight=syncro+hub

 

[AllanD]

From the pictures it seems to me that the synchro collar is on the hub
BACKWARDS.

The common mistake when disassembing one of these transmissions is people taking apart things they don't need to.

 

[IAmTodd]

So the surface in the third picture should be facing fifth gear but the collar should be disassembled and reversed. I assume if that's the case then the dot on the collar above was the one I was referring to. And should face backwards. This would make sense since the needle bearing for fifth gear would have extra play since there is open space between the gear and hub.

I shall go home and play with a few different combinations.

The common mistake when disassembing one of these transmissions is people taking apart things they don't need to.

I'm not terribly certain mine was done by a 'pro'. I don't claim to be but I know when to ask questions when I hit a dead end.

 

[IAmTodd]

So the collar on backwards was my mistake (still learning!) and reviewing my first picture you can clearly see the collar was on the correct direction. I realized this after I have put everything back on the counter shaft to test shift.

I took it back apart and inspected the collar. I noticed that is looks like part of the teeth facing fifth look worn down. I would assume they shouldn't look this way. Would someone be able to give me a second opinion?

Would it be worth my time to track down the updated 30t kit for the rear instead of replacing the collar? I see Southwest Gear has the collar for $55 for the 36t. Wondering what the difference would be to upgrade.

Thanks again for all of your help.

EDIT- just counted the ears on the above piece and it looks like I have the updated 30 count one. Going to go ahead and order a new one of those.

 

[IAmTodd]

So it seems that I've cured the symptom but not the problem. Its locked into fifth but the shifter still moves back and fourth. I can see how these grooves were worn into the slide but the constant shuffle of the slider. Without wildly throwing parts at a junk yard trans, what else could be the issue? I was thinking I may have the shifter bushing spaced wrong but the issue occurred when the bushings were just as indicated by the original slider.

The thought of having to tear the back of this transmission off again makes me sick but it looks like I'll have to go digging again.