The Seal is there to keep out dirt & lawn cuttings etc. So you should get that back on there. Is it leaking oil ?
What transaxle does it have, if you say manual 6 speed Dana. That's not so good.
I just had this happen to mine. The seal popped out and there was watery fluid dripping and all over my wheel(smelled like gear lube to me). The guy at a repair shop down the road said it's fine and that the fluid wasn't anything to worry about. He said the gear lube just gets a little watery and that is what escaped? Sounded odd to me, and he didn't sound very confident. He also didn't know what was in it. First he said oil, then grease, then he said we could fill it, but there are no plugs.
It's a YTA22v46.
After finding no way to put anything in it, I just pushed the seal back on and it hasn't popped out in 5 hrs of mowing.
I do want to sell this mower to my friend so I can upgrade to a larger one, but want to be able to tell him it's fine first.
Thoughts?
TIA!