I just pulled a '91 d series SI transmission out of the junkyard, and before I put it in my girls car I wanted to make sure the internals were relatively ok.

I split the trans to inspect, and as I removed the last few housing bolts, I noticed the case popped apart itself. about .5mm was the gap. I have never seen this before, as previous transmissions i have had to use a rubber mallet to get apart.

in putting it back together after inspection, the gap remains.

Needless to say, I need to use this transmission because the other one has a bad ISB, but this one doesn't want to go back together. The inspection revealed nothing out of the ordinary. The transmission spins and shifts without binding, but there is that .5mm gap that has me nervous. I am wondering if the mainshaft is shimmed really wrong? I did not add or remove any shims. I have alse made sure that the pins on the bottom the shift fork rods are in their slots , so i know it isnt that. Anyone have any thoughts?

 

Is that after you got the C-clip seated on the bearing?

 

Did you assemble the mainshaft correctly? Diff seated all the way?

 

the gap should be about .010", it is the mainshaft thrust washer which gets preloaded when case bolts are tighten down.

.5mm is too much.