Anybody ever swap their trailer hubs over to the Vault maintenance free oil filled hubs? Is there actually a conversion kit or do you have to buy all new axles? Did a little looking last night on the interwebs. Didn't find too much, as far as a conversion kit.

Not sure about how easy the conversion is but I can't imagine difficult, I've looked into it once.
My friend has them factory and had one fail which they caught in time and the company warrantied. Just noticed another one going bad and they just rebuilt themselves due to time. Nice thing is it's easier to visual notice a problem before it destroys everything.

Airtight hubs have a couple options also.

If you have grease zirks in your spindles a good option would be the better oil bath seals, Jack up and pump grease in while spinning the tire till the old grease pushes out the front cap. Unfortunately none of these 3 options are as good as they should be. If our vehicles had bearing issues ever 20k miles instead of 150k we would be pissed! Trailer parts are all junk!

So, its sounding like its not much more beneficial. I have the zirks in my spindles and service the bearings every year. Was looking for a possible alternative, to not have to service bearings every year. Not that its terrible, but one less thing to do, is always better. Thanks for input.

I have used these air tight hubs for years. All salt water, pulling coast to coast. Not 1 failure.