Bearing Maintenance

qhumberd

@ScottG I recently completed the bearings on my 2019 and the axle is similar. I ordered new bearings and seals from etrailer but after disassembly and inspection I found no need to replace it all. I repacked the existing bearings and replaced the rear seal and adjusted the brakes and all was good. I now have an extra set of bearings and a couple of rear seals that travel with me in case of a breakdown on a trip.

qhumberd

And the bearings I inspected from my 2019 rig were identical looking to the replacement etrailer bearings. Both sets were stamped China so Dexter may source from there anyway.

Tampakayaker

qhumberd said:

@ScottG I recently completed the bearings on my 2019 and the axle is similar. I ordered new bearings and seals from etrailer but after disassembly and inspection I found no need to replace it all. I repacked the existing bearings and replaced the rear seal and adjusted the brakes and all was good. I now have an extra set of bearings and a couple of rear seals that travel with me in case of a breakdown on a trip.

How were you able to get the seal out without  damaging it?

When I took them out of my pop ups hubs I couldn't reuse them.

qhumberd

After watching the Dexter video and some others it was almost comical how hard it was for me to remove the first rear seal @Tampakayaker. I thought have I really gotten that weak? I started with a long flat screwdriver and ended up with a large claw hammer before it came out. So it was trashed. I was ready to start drinking. Second one was relatively easy but in no instance can you get a rear seal out without damage, so I bought a set of seals in addition to the new bearing set, which also came with seals. 

ScottG

I was curious about the seals as well. In my extensive experience with trailer wheel bearings (translation: I watched a couple You-Tube videos and did it once--ha ha) the rear seal is often tapped out from the front by whacking on the bearing with a suitable implement to distribute the force. Whether this is a good idea or not, Dexter specifically says not to do it as it may damage the bearing. Hence the recommendation to pry the seal out, which as qhumbard confirms, tends to make a mess of it.

Regardless, given the concern about grease oozing into the brake mechanism, I'd be inclined to replace the seals even if they were still salvageable. 

I do like the idea of carrying an extra bearing kit. As with having a good spare tire, it seems it could make the difference between a moderate nuisance and a major inconvenience.

ColoradoJon

Definitely pry out the seals and replace them.  You can source the bearings and seals at your local automotive store like Autozone or Napa.  I did both seals and bearings on my 2017 last year and it was a relatively easy job

Tampakayaker

qhumberd said:

After watching the Dexter video and some others it was almost comical how hard it was for me to remove the first rear seal @Tampakayaker. I thought have I really gotten that weak? I started with a long flat screwdriver and ended up with a large claw hammer before it came out. So it was trashed. I was ready to start drinking. Second one was relatively easy but in no instance can you get a rear seal out without damage, so I bought a set of seals in addition to the new bearing set, which also came with seals. 

Back in my high school Maputo shop days changing out the wooden and steel rimmed buggy wheels ( not quite that old but sometimes feel it) we used to use a long drift punch and come in from the outside of the hub thru the middle of the bearing and catch the edge of the seal where it was pressed into the hub.  A couple of quick taps on the punch movingit around the seal popped it out. But it was no good after that.  I was just thrown off when you said you kept the new seals u til your explanation of 2 sets.

ScottG

I notice in the Dexter video they specify that sealant should be applied to the new seals. I wonder/suspect if that has to do with resisting pressure created by the EZ-Lube system--something that I understand can potentially pop the rear seal and contaminate the brakes with grease.

I also suspect it may have something to do with why those rear seals are so hard to get out, and why pounding them out with the bearing is specifically contraindicated!  :-)

Horigan

Does anybody know why trailers don't use sealed cartridge bearings, as are used on modern cars?  I can see using cone bearings for boat trailers that get submerged a lot, but I don't understand why dry trailers don't use more modern bearing systems that don't require annual maintenance.  

Dalehelman

cost

N7SHG_Ham

Dexter does make hubs with both oil bath hubs and sealed hubs, but maybe not in the smaller size. Cost! Same reason we don't get disk brakes, they are made but not many trailers use them.

Old school, cheap and they work, so the same old school tech gets used.

Dutch061

Horigan said:

Does anybody know why trailers don't use sealed cartridge bearings, as are used on modern cars?  I can see using cone bearings for boat trailers that get submerged a lot, but I don't understand why dry trailers don't use more modern bearing systems that don't require annual maintenance.  

Here is a link to a company that sells a "wet hub conversion kit" if you wanted to convert and eliminate the need for cleaning, inspecting, and repacking.  

https://www.liqualube.com/ 

Who knows, when I decide to service mine in a few years, I may do this.

Brad

N7SHG_Ham

Still a recommendation for yearly "oil" changes and you would have to drain and pull hub to inspect brakes. It seems you are just changing method of lubing bearings, but still same maintenance interval and maybe easier.

They are correct in saying big trucks use an oil bath hubs, but AFAIK, no requirement for regular oil changes and inspection. I drove truck for three years and had one front wheel hub leak in that time, was about an hour to change and get back on road.

tabiphile

This has been an interesting discussion. I just counted up how many sealed bearings I have had replaced on cars (no lube, run em until they get so loud that you can't stand it)...and over the past years I can recall having 11 of them replaced. The earliest one was at 46,000 miles, many of them were in the 50 to 65,000 mile range and the rest were over 65,000. One car had the same ones replaced several times, at 70,000 mile intervals. All wheel drive cars put the most load on the bearings and consequently have the highest number of bearing issues.
I have never had a bearing failure on an old cone bearing set on either a trailer or a car and that includes a host of old cars and boat trailers. I have been pretty meticulous about re-packing them and I am also extremely careful about how I load the bearings when I assemble wheel. I always use a torque wrench to tighten castellated nut to the manufacturers torque number and then back the nut off to the first slot where the split pin will fit in. 
If you don't 100% follow the 12,000 mile one year recommendation you may get away with it....and especially if you don't put a lot of miles on. But it's a gamble. Once you start doing the service on these you begin to figure out what you can get away with...if the bearings look good and grease is clean every year, sure, go a few more miles next time. But if you don't have that information to base a decision on, do the service.

ScottG

With spring on the horizon I'm turning my thoughts back to this chore.

Does anyone have a current confirmed parts list and source for the bearings, seals, etc. for a 320? I'd like to have the right parts on hand before tearing into the wheel.

I don't think the axles have changed over the years, but Al-Ko was swallowed by Dexter a while back so I'm not sure if the Al-Ko parts listings from older discussions are still relevant.

Thank you for any info!

ScottG

I think I may have found relevant part part numbers on pgs. 78-81 of the attached service manual.

I'm pretty sure we have the 3500lb axle with the 10" x 2-1/4" brakes, but again, any confirmation or specific sources are welcome.

gulfarea

ScottG I also want to at least carry 1 set of bearings for my 2019 320. I also carry a small can of grease. Even if you don't do this work yourself you are way ahead of the game if you have the bearings and the seal to place right in the hand of the person who will be doing the work instead of waiting for him to chase down the parts. Knowing the part numbers for the bearing kit would be a great addition to this forum. I do not have that info as of yet. Art

ScottG

That's my plan, too, @gulfarea. I'm expecting (hoping) I won't need to replace the bearings, but I'd like to have a set to keep in the camper.

From earlier discussion, it sounds like the seals are a different story. They tend to get trashed on disassembly so having those on hand ahead of time is critical. 

WayneW

I just took a look at the bearings on my 2021 320s this weekend. The seal (dexter 010-019-00) cross references to the K71-303-00 ez lube seal listed in the manual for the 3500# axle with 2 1/2” brakes. The outer bearing (L44649) also matches up. So it appears at least the 2021 320s has that same axle. 

gulfarea

I can get the part number right off the bearing and cup but why have to disassemble it just to get the number! I called Dexter and they said there is a letter stamped on the outside of the axel and the axel part number is also under the coroplast stamped on the axel but again I don't want to remove the coroplast bottom just to get a number! I just must be lazy! Anyone knowing the part numbers for seal and bearings sure could save us a lot of time, thanks Art 

Michigan_Mike

Dexter Light Duty Axle Manual

ScottG

@gulfarea, below is a photo of the sticker on the axle, though I'm not sure it helps much for identifying specific parts, as Dexter has sooooo many axles.

Regardless, I've started cross-referencing from a number of sources and am assembling a spreadsheet of part numbers. @WayneW, thanks for the info--the grease seal and outer bearing numbers you provided match those I located, so I think we are on the right track.

I'll post my list when I get it finished.

gulfarea

ScottG thanks for that info, I sure would feel better with those parts in my pocket even if I never needed them! Art

ScottG

Here ya go...

I'm pretty sure these are accurate, but of course make no guarantee as I have yet to disassemble my own hubs. Parts can be ordered directly from Dexter, with etrailer among others offering alternatives. 

Legacy Al-Ko and Hayes P/Ms are courtesy of the late, great RZRBUG from this 2014 discussion. These P/Ns appear to be retired but may come in handy for cross referencing. 

Please give this a look and confirm any parts you can, or let me know of any discrepancies.

N7SHG_Ham

The Dexter axles are very common and parts are available tons of places. I just bought all new hubs, bearings, seals the complete axle end except for the spindle for my 3500 pound axle on a cargo trailer. Some of that may be a bit speciality, but bearings and seals are probably in stock at almost any NAPA store, I know my local store has them. Bearings don't go bad often if lubed, I replaced mine because they were at least 10 years old and I was freshing up the axle ends. My thrust washers were getting pretty groved after about 35k miles. Personally I wouldn't worry about carrying seals and bearings, wouldn't hurt, but likely one more thing to haul around and never need especially if you do yearly service.

ScottG

Good point @N7SHG_Ham. There are lots of sources, including local shops that may well have these common items right in stock.

For bearings, I would go armed with the industry P/N as that should be the same regardless of the actual bearing manufacturer. 

ScottG

Does anyone who has done this happen to recall the size of the castle nut on the axle?

I have adjustable wrenches, but there is a step where the nut is supposed to be torqued to properly seat the bearings, and that is easier to do with a properly sized socket.

N7SHG_Ham

I have the socket, I can look later today.

ScottG

Great--thanks, @N7SHG_Ham!

N7SHG_Ham

1 1/2" socket. Mine is 3/4" drive, so used a 1/2" drive to 3/4" drive to make my 1/2" drive torque wrench usable. Craftsman brand, but any you could find should work.