FWIW the instructions that came with my warn premium hubs recommends using gear oil rather than grease to lube the hub. Done that with all the warn's I'm using and haven't had a problem

 

You need to lock the hubs in a few times a year or this will happen every Fall. I learned my lesson a few years ago...

 

I tried doing that... and infact I bet in the summer, when I go mudding I have my truck in 4x4 more than in the winter. And I did lock the hubs a few times since the last time, but they werent working and I didnt know that. That last time of mudding was a GOOD night of mudding and I was really hard on my truck. So i bet they didnt work after I took them out that day... But for now they are fixed, and My truck WILL NOT GET STUCK. We were driving through 4-5 foot snow drifts yesterday, like nothing... I love my truck and the OBS fords....