2000 Explorer Sport, Trans Case Broke

[fordf1504x4]

Hi, i need to bring up an old problem, 2000 Ford Explorer Sport, automatic overdrive transmission. The servo cover on the passenger side front of the transmission, snap ring popped out of place, case is cracked about an inch around the snap ring slot. I know this is an old problem, I was able to clean the snap ring grove and place the servo cover and snap ring back in, but what i wanted to know is there a problem that causes it to break the case or is the case the problem. I had the same thing happen on my 1990 Aerostar, the difference was the case broke so far around that i was not able to put it back together. I was looking for information as to what causes the problem, it is a pressure problem inside the cover that blows it off or is it a just a case failure problem? I was searching the forum but can't seem to find an answer for sure. Any help would be appreciated, thanks

 

[JK080]

Case failure as far as I know.

 

[fordf1504x4]

ok, thanks, I was just wondering if there was something I needed to do inside the trans to try to prevent it from occurring again or not. thanks again