Ok, need to check it. I did think it had a 37... casting number. Appreciate all your help and expertise on this. I just finished going through Tom Hands book, but it does not get into all the details of the different parts and what is compatible and what is not.
So what can cause the output shaft to move aft and damage the case at the sprag? This trans had some failure that induced a lot of metal and blocked oil ports in both shafts. The rear reverse drum galled the output shaft support and the shaft scored the inside. The sprag inner clutch ring was being driven into the case and scored it pretty bad. What is the output shaft thrust component? You have the cast iron pump and a thrust washer for forward thrust, but it seems like nothing prevents aft thrust from being taken by the case itself. Is that correct?
The output shaft is held in place by the ball bearing in the tail but the shaft moving aft isn't the cause of the sprag race galling the case, the race and drum are free to float for/aft. I believe this damage is caused by lack of lube. BTW, there is a kit to repair that case damage.
https://www.sonnax.com/parts/1828-case-repair-bearingThe input shaft is free to float for/aft within the confines of its thrust washers between the clutch drums; the only way for the output pilot shaft to bottom in the input shaft bore is if the thrust washer(s) between the input and output shafts are missing.
