Leaking t/case seal
I have a 2005 Ford F250 with the 6 L diesel and I have replaced the transfer case output shaft seal three times and every time it has leaked, I'm starting to get sick of replacing them, the first time I believe it happened because my support bearing/bushing for the drive shaft was completely shot so I replaced that and replace the seal as well, the second time right after I took it for a test drive turns out I must have forgotten to tighten down the carrier bearing bolts for the drive shaft so I understand that but now I've replaced the seal again and it was holding for a bit but still took a shit and I pulled it out to find it pretty much welded itself to the flange/ dirt cover on the end of the output shaft. Please tell me what I'm doing wrong, I hate replacing these! A few things I have already done is checked the vent line to the transfer case and it is not clogged I can blow through it just fine, I have also checked the play in the output shaft of the transfer case and there is nothing so I assume my bearings are good inside the transfer case itself, I also tried wiggling it with everything put back together via the drive shaft and there was nothing, no movement at all, is this just bad luck of getting a shitty seal? The first seal iput in was Motorcraft but the second seal I picked up from O'Reilly's, it was supposed to be a good brand seal and that one failed, this third one I picked up from Napa and it's in SKF seal so I am kind of lost. Any input or advice will help! Also side note I tried looking up videos of people doing them but apparently I must be the first one to do one because nobody seems to have a video of them doing one and I can't find anyone else running into the same issue, I am fairly certain I am installing them correctly but there may be other ways.