Trailer Wheel Bearing Grease

I'm in the process of replacing the brake backing plates on my new to me 5th wheel trailer. I'm on the second wheel out of 4 and both had the inside of the brake drum covered with grease. It has a grease zerk on the end of the axle and it comes out a hole between the inner bearing and the grease seal. It looks to me like someone over greased it and pushed grease out past the seal instead of thru the bearing. I have new grease seals and the bearings so far clean up nice, so I'll reuse them. The old grease is very thin, looks like regular gun grease to me. I got a tube of wheel bearing grease from Napa and filled the bearings with grease ready to put the wheel hub back on. How much grease do you put in the center of the hubs? These were packed full, but the Napa grease is thick enough that I highly doubt that the hub ever get hot enough for the grease to run into the bearings. I put about 10 pumps in the center from the outside before installing the outer bearing. Is that enough grease or do I need another tube and fill the center cavity?? Thanks, Chris PS I have seen wheel bearings on new equipment with grease only on the bearings and the cavity is dry.

I was instructed to finger coat the inside of the hub and spindle to prevent rust. Quality grease for wheel bearings is a must. Jim

Thanks

I had a similar situation, turned out I had the wrong seal. The seal fit in the hub, but was about 1/8 to small for the spindle. Talking to the dealer it seems it's a common mistake.

Chris
Google Dexter axle company
Should tell you what you need to know

I always fill the center of the hub half full of grease

Ive never seen the grease from the middle of a hub make it into the bearings. I pack my bearings good and go.

* I dont own a boat trailer. If I did, I would fill the hubs in that application.

nothing in the centre, pack the bgs, and coat the races good and good. i just did a brake job for ny neighbour her and the centre was full of grease and coming out the seals. some people dont know when to quit pumping. i told him to make sure he uses it for one year before thinking of greasing the zerks. he uses it often as its his tool trailer. it was a mess replaced all 4 backing plates with brakes complete. packed the brgss with mystek grease the good stuff. that chep gun grease is useless. it turns to water when warmed up. and what u seen is correct. then zerks are only good on boat trailers when they back them in the water then you need a way to get the water out. stop and think that brg is not turning that super fast on a trailer, not like them 8 inch boat wheels.

If you can get them oil hubs are much less work and maintenance. Just look at the window on the hub if no oil just fill it if oil on inside if tire seal time. The best seals if you can get are Stemco seals hands down I get 10 years on the semi and all the others only about 3 if I'm lucky. I've used or tried them all. C/R Scotseal,National,Mechanix by Barrier and they just don't last or work. This is on 3 trailers and 2 tractors over more than 20 years.

You're supposed to grease EZ-Lube hubs until grease comes back out the outer bearing. It sounds like the seals failed; maybe the bearings weren't properly pre-loaded.

Leave the center empty. And don't use the grease zero again.

I have always filled the hub to the level of the bearings, not solid full. The oil from the grease is supposed to leach into the bearing. As to my trailer bearings that have grease fittings and a rubber cap/seal on the outside I put one or maybe two pumps of grease in them every year or two. So far so good.

No! Pack the bearings. Don't just smear grease on them and think it's going to make it's way in. Either get a cheap packer or use the old blob of grease on your palm and force the grease through the large side of the bearing until it comes out the other side. Once packed, put a layer on the bearing race and put it back together. Do this for both bearings. No need for grease in the center cavity. Good grease will stay in the bearings and grease in the center cavity isn't going to magically make it's way into the bearings.

On axles with fitting, I figure if that inner cavity is not full, every pump you put in just goes into the air space and never gets near the bearings. So the right way is to pump until you see some coming back at you through the outer bearing. But thats all. They are for people that never want to disassemble and hand repack. Properly hand packed will go quite a while if you remember to redo.

SOME axles have a hole drilled through the axle towards and behind the backing plate. SO... that when the space is full, excess grease will be sent through the hole and expunged behind the backing plate. ONLY this style hub can be greased constantly, at least till the hole plugs up. Boat hubs are greased till the spring cover starts to move out. This is only to keep a high pressure on the hub so that water can not come IN. Most folks dont know to look for the telltale indicator to move out showing enough pressure is on the hub. Also for boat trailers you can use a graphite based grease or it will eat up the bearing in the presence of moisture.

Is this a boat trailer that the hubs regularly get immersed in water, or a trailer that gets pulled 10,000s miles a year? If not just repack the bearings periodically and ignore the grease jerks.

I have been in hundreds of wheel bearings for cars and trucks. The factory packed the bearings and wiped a finger full of grease inside of the hubs. The only bearings I will use a gun on are boat trailers and grease them when you hook up so they have some pressure on them when you back in the water .