2004 New Holland TS100a drive shaft leaking on the rear seal

[dbbtractor]

It's the drive shaft that leads from the rear end to the front differential, we have replaced the seal and it still leaked then we did the seal and o-ring and it still leaks. I'm not the one that replaced it, it was my dad and he doesn't pay attention to stuff as good as I do so there could have been another problem like metal worn off of something which caused it to not have a could seal. I do know that the carrier bearing (I think is what it's called) that supports the middle of the driveshaft was loose. But it started leaking almost right after we fixed it and drove it. The trans case also bolts together right there which means there痴 a gasket there, I had the suspicion that it was leaking through there because the paint has come off in a spot right on the gasket but it痴 clear that it痴 coming from the seal.