pplusent

I have a 93 4runner that seems to have an 1100 stall converter instead of the 2200 converter that is called for.
I need to know what difference this will make?
I am having a problem with cracking cases at the center support as well on this tranny and I don't know if it is related? this is the 3rd tranny I have had in the car, one stock used tranny, one someone else rebuilt and the one that is in there now that I rebuilt which runs perfect other than not locking in overdrive which I was planning to fix but I think the case has now cracked.
Whenever I have run these trannys up over 60mph they crack and blow out a burst of fluid, but once cleaned up they don't leak a drop if kept under 60mpg.
First one cracked during an emissions test, 10 qt's of fluid on their floor! Needless to say they didn't like my truck anymore.
looking for ideas on the issue, so I can get my 4runner named Satan on the road again!