HELP!!!Driver's side axle installation into transmission Differential case.

I have a 1994 toyota camry. The car runs fine, the transmission is strong except the left driver's side axle will not stay fitted into the transmission..Whenever I drove I would feel and hear a loud thud coming from the front left side of the car whenever I would turn the wheel all the way to the left and make a trun. I thought it was just an axle replacement upon replacing the axle I found there was no gear oil in the differential casing and had leaked out through the left axle housing... (the transmission fluid is in one part of the tranny and the gear oil is in the differential housing of the tranny where the axles are inserted and set)..I replaced the axle and the seal only to find it was still leaking and I still would get the occasional thud...Also when steering, the steering wheel would seem a little numb when turning left or vearing left...Going to a different shop thinking it was a bad mechanic the new mechanic tried the same procedure and found that after a short test drive the axle would set itself free from the transmission housing...The clip that holds the axle in place was a little mutilated and the gear oil continued to leak...The transmission case is not cracked..I would like to know what mechanisms actually hold the axle in place and can I just replace the parts inside the differential housing of the transmission or am I going to get shafted into buying a whole new transmission, seeing as my transmission runs and shifts fine....HELP!!!!Any diagrams or explanations would be GREATLY appreciated