I have a 2015 Trailstar duel axle with Vortex hubs. One started leaking grease/oil yesterday, just found it . From what I understand of the Vortex hubs its all sealed and self-contained, so there's no way to add grease? Once they leak, are they shot and have to be replaced immediately? Does anyone know how to find the model number for the hub and how difficult are they to replace? Can anyone work on these or only certain places? I've got a 250 mile tow coming up in 2 days, I've got to get this situation resolved quick! Thanks for any help you can offer.