This is the third one in the last four years. The first one went in 2013, the second one in September of 2015, and this last one went last Thursday. After the first one went I changed all four of my cool hubs to a different cool hub, that doesn't have the plastic cap to see the level of oil. These have a rubber plug the comes off so you can see the oil level. Now they have a Vortex hub with grease. There must be a reason they keep changing this falled system. Now I am going to change all four again. I would like some feedback on the Vortex hub, I am sure that I am not the only one with this problem. Thanks in advance. eagle521