Center lube hubs

[Rock]

Reading on just about all the Rv web sites greasing the center lube bearings comes up and most info is b.s. As a life time salt water boater this is what I have found. Salt water u lube everytime because water gets behind the rubber seal. When pumping grease especially when cold out can cause the seal to leak. On a Rv u should only need to lube twice yearly and I would do it in the warm parts of the year. The first time u grease the center of the hub between bearings will be empty. The factory just puts in greased bearings. The first fill might take 20 pumps until the grease starts pushing out of the outer bearing. The trick is to get a cold drink and pump at a very slow pace. This allows the grease to move thru the bearings, pump fast and it will blow out the rear seal and coat the brakes. Since the Rv wheels are not submerged in water (hopefully) u only need to do this twice a year. After the second or third fill it should only take a few pumps to have grease push out of the outer bearing. Remember to wipe the excess grease out of the cap before u put the rubber plug back in. If u do not when the brakes get hot it will push out under the rubber plug or the inner seal when hot from expansion so wipe out as much grease as u can before putting the plug back in. I have blown several seals from pumping to fast and seals do go bad. This system was designed for boaters to allow fresh grease to push any water out of the bearings. I only removed my hub and bearings every three years for inspection and never had a problem on a saltwater boat. I do the same on my Rv and it does not go under saltwater. If ur brakes chatter u probably had a seal failure. Over greasing is a myth pumping to fast is what blows a seal or cold thick grease or not removing the excess grease under the cap. I do not have that problem in Fl
Rock

[DocBrown]

With RV trailer wheels you don't even need to do this twice a year. This is my second trailer with EZLube axles. I only do them every couple of years. I had my last trailer for 10 years and when inspecting the bearings they were always in perfect condition and properly greased.

[Rock]

The problem is the bearings are not encase sealed. So the grease will push out somewhat underload and when hot from breaking. It only takes 30 min to grease a tri axle. If u had a sealed bearing that is different. Towing 15k puts a pressure load and when hot grease lose occures. All the dealers will tell u that u need to pull the hubs yearly and that is bs just a money maker for them. Grease twice yearly (slowly) and u will never have a problem and if u do it was a China bearing or bad seal. Always use Timkin bearing and not Chinese junk.
Rock

[Gone campin]

The other key is to have the wheel off the ground and rotate it slowly while pumping in the grease (per Dexter) - it will help keep it from blowing out the seal...

[Rock]

I agree with jacking but on some big FW it is a job. Greased saltwater trailer every use and just pump very slowly and never had a problem
Rock