904 Transmission Stopped Going Into Gear

Results of more investigation:

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I did reassemble the pump with an alignment clamp.


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The rear band is loose enough to let the reverse drum move by hand. I can push it to the rear and feel it solidly bottom out against the inside of the case.

I removed the speedometer gear and looked at the rear bearing. It looked fine.

For fun, I took the entire tailhousing off and tried reassembling the drums.

I think I found the problem, see video below.



These are the conditions in the video:

-Tailhousing off (obviously)
-No clutches in any drums
-No direct drum band
-No bump o-ring or gasket
-Retaining clip on output shaft installed (feels fairly snug in its slot)

Is there supposed be this much end play at this point?

When I assemble the drums while the trans is in this state, it all goes together and when the pump is tightened, the input shaft spins freely and has endplay. However, if I slide the tailhousing on and tighten its bolts, the input shaft no longer spins freely or has endplay. Everything gets "bound up" again.

So it has something to do with the input and output shafts getting pressed together too hard when the pump pushed the input shaft back and the tailhousing bearing pushes the output shaft forward?....