Repack bearings

[Guest]

So this is where I have a slight issue. MORryde says no, but Kodiak has a kit for it https://www.etrailer.com/p-XLPROLUBE2440KIT.html MORryde sells suspension components. They probably have a lot of knowledge on axles and components, BUT --- https://www.kodiaktrailer.com/dexko-...ets-to-kodiak/ So Dexter now owns Kodiak.... Kodiak sells a conversion kit. One would think if Dexter bought a company that sells something that is detrimental they would kill the product line. And Kodiak specializes in hubs and brakes.

I might do one axle and see how it fares. I can always go back to grease. Yes I have been there and done that on axle failure with grease. I know what it looks like when bearings weld them selves to the shaft and you cannot find the hub, rim, or tire. Dexter has a very very professional quick acting warranty dept. Called Monday new axles with springs and bolts by Thursday and they found an installer to do the work where the trailer was located.

Joseph,

The oil bath would not run any hotter than a greased hub and if the oil can take the temperatures is should not be an issue. But large trucks to Robs point have much larger bearings and much more oil while rotation is also much slower. Ive seen these on boat trailers and they seem to work well. I'm curious what the benefit is for an RV? With marine apps you look for a discoloration in the hub oil to tell you that water intrusion has occurred. In our applications, we would never see water intrusion. Outside of that, serviceability would be much easier with oil bath hubs....if they seal. I would not trust a conversion.
Jim

[Jlawles2]

Guest Jim, I cannot find the drum for the D52 axle, but in the parts catalogue https://www.dexteraxle.com/user_area...te_catalog.pdf on page 49, they list an oil seal and a EZ-Lube seal (they are the same part number BTW).

It's a bit funny because on my D70 axles they have different seals for the oil and E-Z lube axles and a different drum. The drum I think is different because the oil cap is threaded vs the grease cap being an interference fit. The seal OD is the same, but the grease seal is a little smaller ID (note spindle is the same on both). This leads me to think on a 7k axle the hub casting is the same, uses the same bearings, therefore has same internal volume.

I challenge MORryde in there statements about volume for compression since grease will have the same or more heating of both the grease and the air inside the chamber. I have not worked on class 8 hubs myself, but been around a few of them. Their internal volumes are more simply because of the required design to support the weights. Some of the equipment I am around at work carries 15 tonnes (yes that's a valid number) per axle group. I think there are 4 bearing in the group, but still thats equates to a 33,000 lb axle and they run grease. Grease limits speed on the axle group even unloaded as grease bearings tend to run warmer than oil bath bearings. I think they have oil bath conversions for some of the newer stuff.

What advantage would oil bath have over grease.... Inspection - look at hub end, oil at indicator line = good, oil proper color = not overheated. Mess during maintenance = wash between the 2. Rodside repair with parts on hand, oil = easier and faster to install less chance of error in end play setting due to impaction of grease between surfaces, grease = mess to pack mess during install, grease between cone and cup leads to improper endplay setting. Heating as mentioned oil bath tend to run cooler. Heat = enemy. Cost, oil seals are stupid priced at 4x the cost vs grease seals. However I think the oil seal is 2 pc thus no wear on the spindle vs grease double lip seal riding on the spindle potentially wearing a groove in to the seating surface.

https://www.etrailer.com/Trailer-Bea...BE2440KIT.html not really a bad price for the kit when you consider you are servicing 2 axles. The replacement seals alone cost more than the kit.

[ThePowells]

Geez, now y'all done went and made me start wondering.. Right now, have two short weekend trips planned before Indiana. I'm planning to pull hubs and bearings before we go on the short ones and now I am thinking about trying an experiment. I might just repack one axle and convert the other and leave the center covers off. Then when on the way to the Raleigh, I can go about 15 miles then go from 65-70 MPH to a stop in a safe place without using trailer brakes, and then take temps on all 4 hubs and see what we have. I just wouldn't want having a difference in brake adjustment making a difference in a reading. That should give me a apples to apples comparison just to see which actually does run cooler.

[Guest]

Guest Jim, I cannot find the drum for the D52 axle, but in the parts catalogue https://www.dexteraxle.com/user_area...te_catalog.pdf on page 49, they list an oil seal and a EZ-Lube seal (they are the same part number BTW).

It's a bit funny because on my D70 axles they have different seals for the oil and E-Z lube axles and a different drum. The drum I think is different because the oil cap is threaded vs the grease cap being an interference fit. The seal OD is the same, but the grease seal is a little smaller ID (note spindle is the same on both). This leads me to think on a 7k axle the hub casting is the same, uses the same bearings, therefore has same internal volume.

I challenge MORryde in there statements about volume for compression since grease will have the same or more heating of both the grease and the air inside the chamber. I have not worked on class 8 hubs myself, but been around a few of them. Their internal volumes are more simply because of the required design to support the weights. Some of the equipment I am around at work carries 15 tonnes (yes that's a valid number) per axle group. I think there are 4 bearing in the group, but still thats equates to a 33,000 lb axle and they run grease. Grease limits speed on the axle group even unloaded as grease bearings tend to run warmer than oil bath bearings. I think they have oil bath conversions for some of the newer stuff.

What advantage would oil bath have over grease.... Inspection - look at hub end, oil at indicator line = good, oil proper color = not overheated. Mess during maintenance = wash between the 2. Rodside repair with parts on hand, oil = easier and faster to install less chance of error in end play setting due to impaction of grease between surfaces, grease = mess to pack mess during install, grease between cone and cup leads to improper endplay setting. Heating as mentioned oil bath tend to run cooler. Heat = enemy. Cost, oil seals are stupid priced at 4x the cost vs grease seals. However I think the oil seal is 2 pc thus no wear on the spindle vs grease double lip seal riding on the spindle potentially wearing a groove in to the seating surface.

https://www.etrailer.com/Trailer-Bea...BE2440KIT.html not really a bad price for the kit when you consider you are servicing 2 axles. The replacement seals alone cost more than the kit.

Joseph,

I believe we are in agreement. Except I would not use a press in conversion kit. True oil bath hubs are either a threaded hub with an O ring for the cap or a bolt on cap with gasket that's similar to whats used on the heavy trucks. The conversions looks too risky to me. A leak and your broke down. With grease, you can loose the cap and you will get to your destination. The inspection part really only applies to marine applications (trailers) since we would never see water intrusion on a land yacht.

Jim

[familytruckster4]

I had an interesting conversation with a friend of mine who runs his family's truck/trailer/sales/repair business (3rd generation) about using wet hubs. He commented that their experience is that they arent any more reliable. He also stated that he had seen some folks switch back to greased bearings from the wet hubs.
I believe the tapered bearings have been common in GM vehicles since the late 50's. I know both my 57 Chevys had ball bearings and my 64 Chevy has tapered.

[Guest]

I had an interesting conversation with a friend of mine who runs his family's truck/trailer/sales/repair business (3rd generation) about using wet hubs. He commented that their experience is that they arent any more reliable. He also stated that he had seen some folks switch back to greased bearings from the wet hubs.
I believe the tapered bearings have been common in GM vehicles since the late 50's. I know both my 57 Chevys had ball bearings and my 64 Chevy has tapered.

If the bearing remains lubricated, there would be no significant difference, except serviceability. In fact years ago when I serviced the rear axles I packed the bearings with grease because it would take time for the gear oil to reach the bearings. This ensured they were lubricated. Also the rear axles had whats referred to as a speedy sleeve where a small sleeve was pressed over the rear axle in the sealing area. When this became grooved, you tap the sleeve with a ball peen hammer and it stretches the material to come loose. Using a tool to install a new sleeve and the axle is as good as new.

Jim

[pauldridge]

This forum is a wealth of information and I appreciate its existence. That said, I have noticed a common trend for "contributors" who like to pass along rumors/mis-information they have read elsewhere, but have not experienced or observed themselves, and the rumors seem to perpetuate themselves.

Nothing could be more frequent than discussions about wheel bearing maintenance. I respect those who have chosen to remove all 4 wheels and drums, pry out the rear bearing seals, and repack their bearings every few thousands of miles, and who poo-poo the innovative external greasing feature of most all of the axles these days.

But I have to ask.. when was the last time you packed the bearings in your 5,000+ pound Ford truck, in spite of driving 40-50k miles per year? The basic construct of most vehicle bearings is pretty much identical to our trailers.

I almost drank the Koolaid myself regarding rash warnings about using the external grease nipples ("you will blow out the rear seal with too much pressure").

That was before I decided to look at the official company videos from both Lippert and Dexter (not just a video from some shade tree mechanic holding the "camera" in one hand.

If you look at the internal construction of these new hubs, you will see that grease flows through the center of the axle exiting BEHIND the inner bearing, then travels through the bearing along the axle up to the outer bearing, where it comes on through *under gentle grease gun pressure, and finally exists at the front of the bearing and hub.

Here is Dexter's official video describing the greasing process.. Lippert's is near-identical: https://www.youtube.com/watch?v=XT0RKDGgDm8

Yes, both companies DO suggest that you jack up (without removing wheel or drum) and turn the wheel slowly while greasing to assure complete propagation, and continue pumping your gun until you see all the old grease exiting the front and new grease pushing from behind.

So.. I submit a few points based on manufacturer's data, not baseless rumor:
1) No, 2-3 pumps of the grease gun will accomplish virtually nothing. It DOES take a good bit of grease to displace the old grease in both bearings and the internal hub housing.
2) It would be extremely unlikely to "blow" a rear seal, since there is never any significant restriction to the grease's path through both bearings before exiting the front. You could pump a gallon of grease through that bearing, and all you would get would be a huge glob of grease coming out around the outer bearing.

Sure, I suppose there is some value in "inspecting" the bearings from time to time, just as you could inspect the same on your tow vehicle, or maybe even your driveshaft bearings.

For me, I'll just follow the axle manufacturer's guidance (sadly missing from any documentation provided by the trailer manufacturer), spend about 5-10 minutes per wheel, perhaps every 10,000 miles or so, and used the saved time for another margarita!

[Guest]

pauldridge I agree with you in most of your post since marine trailers are greased on a regular basis and I've not seen any seals pushed out with a hand held grease gun. But the annual or 10K mile recommended bearing inspection is there so folks actually looks at bearings, seals and brakes so eliminate or greatly reduce the potential for a failure. Vehicle bearings differ today where to your point used to be tapered years ago and folks would go for years without servicing those. But vehicles do not endure the punishment of a camper with much more mass sitting on an unrefined suspension.

Jim

[ncitro]

pauldridge I have to agree with Jim here, while the use of the zerk may be debatable, that same axle manufacturer's guidance states to visually inspect the bearing, which is impossible without pulling the assembly apart.

[Cate&Rob]

pauldridge

Welcome to our owners technical forum. When you have a chance, have a look at our welcome post. https://gdrvowners.com/forum/main-fo...to-new-members . This will help you set up your signature and navigate the forum.

Your perspective on using the zerk fitting to replenish the bearing grease is well stated. Many of us will disagree for all the reasons that I am sure you already know. A respectful "agree to disagree" perspective is a cornerstone of this forum.

I would challenge your statement that you have "noticed a common trend for "contributors" who like to pass along rumors/mis-information they have read elsewhere, but have not experienced or observed themselves". Many of us on this forum who do follow the trailer manufacturer's recommendation to inspect brakes and bearings annually are speaking from years of first hand experience when we choose to do this. Most of us have the personal experience of finding something that needed repair before it failed completely, that would never have been discovered by pumping new grease into the hub.

Rob

[Jlawles2]

I've done axle greasing both ways. Yes the zerk is quick and easy. However at some point in time to completely replenish the grease in the hub would be impossible due to the fluid dynamics of the grease. It's best to occasionally remove and replace the hubs to check for various things such as bearing colorization due to excessive heat.

[Guest]

I would have to second Robs comment on rumors and so on being spread here from other places. I've also not seen this here where this forum operates at a very high level and is what makes it so special.

Jim

[ThePowells]

pauldridge Welcome to the technical forum! I would have to disagree about the comparison of wheel bearings from the truck to the trailer. My 3500 has sealed front wheel hubs that cannot be disassembled or inspected other than to rotate them and listen. My rear bearings are much larger and are oil bath as I am sure all 3500 and 2500 rear hubs are. I also am pretty sure that the interval is designed more for routine inspection than than anything. Am I fanatical about following this interval?, no. We have had ours for 19 months, but nowhere near the 10K. They are on my short list to do before our late July weekend trip. Had we not been sitting as much, they would have been done a long time ago. I have always suggested a short first inspection interval simply because the LCI and Dexter are not going to use the same quality grease or bearings that most of us would. I just did a repack on a set of LCI axles on a horse trailer for a friend. Four years old and less than 10K miles and resulted in two sets of bearings and all of the plastic dust covers. The grease was just slightly less runny than over easy eggs. I don't expect that my grease will be much better and I will have the correct part numbers for spares. Hopefully this will be the only time to pull these down.

[familytruckster4]

My 2012 Open range and my 2021 Reflection 337RLS both had the seals blown out by being over greased at some point before I took delivery, the grease in the Reflection appeared to be consistently the same color and looked to be from the same source through out. Both trailers required replacement of the entire brake system and the Reflection had one drum replaced due to the amount of contamination (Dexters call). The repairs on the Reflection cost Dexter well over $400 retail in parts.
Either I am very unlucky or Dexter has a big problem considering 66% of the new trailers I have purchased in the last 10 yrs have had the brakes ruined by overzealous greasing.
I still contend that a properly installed trailer hub does not require additional grease between repacks especially if you follow Dexters yearly schedule.

[Cate&Rob]

The cause of early seal failure (in my opinion) is assembling dry seals on to dry spindles. This was a big problem on new LCI axles, a few years ago. In my case, I had three hubs with greased brakes and one where the seal held the grease back. The three that leaked had distinct black lines (see attached picture) where the lips of the dry seals had burned off, spinning against the dry spindle, probably in the first few miles. The seal that held, left no witness marks on the spindle. It had randomly received enough grease to survive.

When I replace a seal, I polish the spindle and make sure that the seal lips and the spindle surface are well greased. I have had no further problems.

Rob