Transaxle Seal

Ok Ok... I have a 1995 Saturn SL1 and it had a leaky transaxle seal. So i struggle and finally get the old one out. Well before I put the new one in I see that there is a snap-ring in seat of the transaxle. I was just wondering what purpose it serves because I've never seen anything like it. I got the seal in and it doesn't appear to be leaking but who knows. If anyone knows what this is for could you please describe its use.

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there are two snap rings per side. one retains the axle seal on the out side. the other one i don't know for a fact but i beleave it is a selective snap ring that controls differencal endplay.

Thanks for the information man. I always like when someone helps filling in the blanks.