A-904 Pump front seal replacement.

Rock auto sells them.....I just bought 3 of them from the local trans supplier...14 dollars for 3 of them....about 4.00 each....

the vent is in the front...but i have never seen a vent leak on a 904.....I have left the pump bolts loose....and it leaked...lol

Is there a possibility that fluid may leak via the pump vent? and if this is the case, what can be causing it? maybe oil overfill?