Flushing grease on axle with zerk

H20Rat

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On paper, the Bearing Buddies are a good plan. In practice, maybe not so much. If the hub is full of grease, there's really no need to pressurize it. That's overkill?

Thermal expansion... Lets say you start towing on a cool morning at 50 degrees, and by mid-afternoon you are still towing and your bearing temp is up to 120 degrees. There is now 5% (4.9% to be exact) more grease in there. Either you have a spring system (bearing buddy), empty air space, or blown seals. No other option.
 

ahicks

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So, your point? You are saying Bearing Buddies are NOT a good plan when combined with Dexter's system?

Though not real keen on the plan, I guess I'm thinking that unless you've pumped so much grease in through the Bearing Buddy you've collapsed the spring totally, the spring would allow for SOME expansion.
 

dingbat

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I'm suspecting you haven't read the entire thread. The pic in the first post clearly shows the Dexter design that will leave the hub full of grease prior to exiting from the outer bearing
Been running the Dexter system in your picture since 2006. Matter of flushed all four hubs on my Loadrite trailer yesterday. I will garuntee you the hubs are nowhere close to being full.

The hubs are not pressurized when greasing so the grease takes the path of least resistance which is straight out the front of the hub. There is no pressure to force the grease to expand and fill into the outer cavity of the hub.

BTW: your axle takes a special sized rear seal. Did you get the right one?
 

dingbat

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So, your point? You are saying Bearing Buddies are NOT a good plan when combined with Dexter's system?
It’s one or the other....you can’t do both.

You either fixed the dexter system and use it as designed or you knock the zerk off the axle and go with bearing buddies. Your choice
 

bigdee

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Thermal expansion... Lets say you start towing on a cool morning at 50 degrees, and by mid-afternoon you are still towing and your bearing temp is up to 120 degrees. There is now 5% (4.9% to be exact) more grease in there. Either you have a spring system (bearing buddy), empty air space, or blown seals. No other option.

I have always ran BBs and have never had any issues. My 1989 pontoon trailer bearings have never been serviced except for an occasional shot of grease to center the piston. I check every season for noise and play and it checks ok. If it didn't I would service the hub/bearings. Stop and think about it,nobody obsesses this much about the wheel bearings in their vehicles.
 

bruceb58

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Personally, I prefer a buddy bearing system with drum brakes. With discs you can get away with using the ez-lube system since you can see if you blow out your rear seal which is very common. Go to any RV forum and see how many people stopped using the EZ-Lube system after coating their brakes with grease.

On my new travel trailer that has EZ-Lube, I will be manually packing the bearings. On my pontoon trailer with EZ-Lube, the rear seals leaked on all the wheels and the inner bearings were pitted due to water intrusion.
 

bhollehday

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Personally, I prefer a buddy bearing system with drum brakes. With discs you can get away with using the ez-lube system since you can see if you blow out your rear seal which is very common. Go to any RV forum and see how many people stopped using the EZ-Lube system after coating their brakes with grease.

On my new travel trailer that has EZ-Lube, I will be manually packing the bearings. On my pontoon trailer with EZ-Lube, the rear seals leaked on all the wheels and the inner bearings were pitted due to water intrusion.

So if I get rid of the EZ lube system, then that means I would use the bearing buddies, and remove the zerk fitting on the dexter axle, correct? You would keep grease packed in teh bearing buddy and make sure you have good rear seals to keep the small pressure load? Is this what your doing?
 

ahicks

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I've been using the Dexter system since they came out with it, without a single issue, ever. If you follow the very simple directions there's a very good chance you won't have an issue either.

As far as the people that have had issues on another (RV) forum, that's kind of like saying you can expect a blown tire. You see a lot of complaints about those too. People complain when "stuff happens". The people without issues are generally silent. I think a lot of times it comes down to the fact you can't fix stupid.....

Bottom line, Dexter axle has an OUTSTANDING reputation. That's why you find them under so many rigs. If they design, test, and produce a system that been in use as long as this one has, and are STILL using it, I think it safe to say it's a trustworthy system.

When you add something like the Buddy Bearing system to Dexter's system, you are complicating the issue. To answer your question, if you're going to run the Buddy Bearings, there's no need to mess with the zerks installed in the axle. Just forget they are there, and use the Buddy Bearings as designed.
 

bhollehday

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I've been using the Dexter system since they came out with it, without a single issue, ever. If you follow the very simple directions there's a very good chance you won't have an issue either.

As far as the people that have had issues on another (RV) forum, that's kind of like saying you can expect a blown tire. You see a lot of complaints about those too. People complain when "stuff happens". The people without issues are generally silent. I think a lot of times it comes down to the fact you can't fix stupid.....

Bottom line, Dexter axle has an OUTSTANDING reputation. That's why you find them under so many rigs. If they design, test, and produce a system that been in use as long as this one has, and are STILL using it, I think it safe to say it's a trustworthy system.

When you add something like the Buddy Bearing system to Dexter's system, you are complicating the issue. To answer your question, if you're going to run the Buddy Bearings, there's no need to mess with the zerks installed in the axle. Just forget they are there, and use the Buddy Bearings as designed.

But if the zerks are not removed from the dexter axle, then grease does not reach the bearings, correct? Seems like you would either use the dexter axle zerks as intended, and the bearing buddy to keep the system pressurized and sealed, or else remove the dexter zerks and use the bearing buddy to keep the dexter system filled, as well as pressurized?
 

Maclin

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The end of the Dexter is not sealed, with the type BB caps you have that can clear the zerk, the grease pumped in from the BB zerk will "see" the bearings.
 

dingbat

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It's been a while but if I remember correctly, the zerk fitting interferes with the plunger in the BB keeping it from bottoming it out. You have to remove the zerk to install the BB.

The EZ lube and bearing buddy systems are both "pressurized" systems. The EZ lube depends on thermal expansion to generate a positive pressure inside the hub and BB uses a spring.

20545IEU-dexter-ez-lube-endunit-01.jpg
bearingbuddycutaway.gif
 
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bhollehday

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It's been a while but if I remember correctly, the zerk fitting interferes with the plunger in the BB keeping it from bottoming it out. You have to remove the zerk to install the BB.

The EZ lube and bearing buddy systems are both "pressurized" systems. The EZ lube depends on thermal expansion to generate a positive pressure inside the hub and BB uses a spring.

[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/www.theoempartsstore.com\/images\/T\/20545IEU-dexter-ez-lube-endunit-01.jpg"**[/IMG2][IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/www.sturdybuiltonline.com\/assets\/images\/Hubs\/BearingBuddy\/bearingbuddycutaway.gif"**[/IMG2]

So what do people prefer with these systems? What method seems to seal the best? I dont know what condition my real seal is in, but when I pump grease, you can see a small amount come out of the back of the axle until it reaches the front and then comes out there.

I keep reading that EZ lube is great, but when it comes to water, BB will keep the water out. Maybe using both is the key, but only using the BB's as a water tight seal to keep water out? And when filling and packing use the EZ lube system?
 

dingbat

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So what do people prefer with these systems? What method seems to seal the best? I dont know what condition my real seal is in, but when I pump grease, you can see a small amount come out of the back of the axle until it reaches the front and then comes out there.
Both systems rely on the integrity rear seal. If grease is leaking past the rear seal, it's bad... replace it. Proper maintenance is the key to any system. Neglect either system and you will not get favorable results.

Opinion are like rear ends....everybody has one.

The guys using BB think they are the best and the guys using EZ think they are the best system. Both systems have been around for a while so obliviously they both work.....

Pick your poison and go for it. It's easy enough to change down the road
 

Cortes100

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:juggle:.....don't over think this. Both system work fine, but you have to start with good bearings and seals.

On my last boat, I had bearing buddies. From brand new bearings were set up properly and greased. Then checked BB's every few outings, shot of grease here and there to keep spring loaded. When I sold boat 8 years later, bearings were still perfect.
New boat/trailer has the EZ lubes. Again I check from brand new, set up properly, and find these a better design IMO.. Only had for one season so far, so can't say anything about longevity. But it seems better since the new grease can get to the back bearing.
FWIW, I visit several lakes in my area, so the trailer is in/out of the water all the time.
 

ahicks

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Agreed, if you're seeing grease leaking from the inside seal, it's needs to be replaced!

When you have it apart, have a good close look at the axle in the area that seal runs on. If you see any rust or pitting there, you'll need to take care of that prior to reassembly.
 
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