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View Full Version : oil bath hubs vs. grease systems



Darren J
27-10-2013, 10:16 AM
Hi,
Just looking for experiences or opinions on oil bath systems for trailer hubs. I am looking at a new us built trailer where I have choices of a grease lube system (that allows grease to be pumped through the centre of the stub which then forces it out of the front of the hub) or oilbath. I am told the oil bath is very good butif the rear seals fail or do not seat perfectly you will drop all of the oil, a problem that grease systems would not have.

Any comments would be greatly appreciated.

Cheers.

cormorant
27-10-2013, 10:39 AM
Durahub are using a mixture of oil and grease as a option so even with a seal leak/ failure you will not have a dead bearing as long as you check them all the time. The seals running on stainless sleeves should be very long lived and reliable.

Grease- well I am yet to see a system that actually does move a thick marine grade bearing grease from back of hub through both bearings. It is the inner bearing that is the major failure point not the outer in my experience.

What ever you get make sure you get spares of all consumables as some of the sizes are not as easily found here and you don't want to be hanging around waiting if there is ever a breakdown.

Darren J
27-10-2013, 10:52 AM
Thanks for the reply. I waslooking at eliminator torsion axles which have a removable stub. Getting spares of those included, but also plenty of bearings as I believe the larger sizes being supplied can be expensive (and sometimes scarce) for supply here. The grease system does pump to the inner bearing first. I figure they will need annual maintenance like any other bearing.

I guess I am keen to see if there are real advantages with oil bath.

Muddy Toes
27-10-2013, 10:59 AM
I got my trailer built over there by ezloader and had oil bath hubs fitted. I just pulled it all apart the other day to see how it was all going after over three years of constant use, high miles and zero maintenance to find the bearings in perfect condition, no oil lost and everything in tip top condition.......

Mike Delisser
27-10-2013, 11:19 AM
I've run a DuraHub oil bath system on my trailer for 5 years until just 2 weeks ago. I still think they are great but 1 of the rear seals just started leaking. I didn't have much time and was about to leave on a 500k round trip to BP Dam so I just wacked a Bearing Buddy (grease) on the suspect wheel. When I get around to it I'll definitely be going back to the oil bath system.
My trailers have done a lot miles with bass comps from the Hunter Valley in NSW up to Cania near Monto QLD, and saltwater in between, maybe up to to 15,000km some years, and I've used both grease and oil. The grease was ok, I'd pump a tiny bit of grease in every 2nd trip and pull them off to check the bearings once a year. I've never had a major failure but maybe every 2nd year I'd notice a little "pitting" on a bearing so I'd install a new full set, inner and out inc races.
I didn't plan on switching to oil, but the DuraHubs were on a 2nd hand boat & trailer I bought 5 years ago. I checked the bearings soon after and they were perfect, checked them again 12 months later and they were still perfect. And I checked both sides 2 weeks ago when I put the Bearing Buddy on (now at least 5 years old) and the bearings were still in perfect condition.
And the oil didn't all leak out either, the level just dropped a bit on a 500km drive and went a fraction milky after launching 6 times over the weekend. They have a glass window so you can inspect the oil. I just topped it up before I drove home.
When I get time I'll lap the axle and re-install the Durra Hub. I might even glue on a shim for a perfect leakproof seal.
Cheers

Out-Station
27-10-2013, 06:57 PM
I stick 20mls of heavy gear oil into the hub with an oil syringe before I stick the front bearing in/on. Everything else standard marine setup with packed bearing, marines seals and caps (not buddies), cap, and marine seal sealed with Loctite 515. Not a 100% oil bath setup but more an oil/grease slurry effect (liquid enough to run back into the bearing). Works great, simple, cheap without stub surface seal issues of durahubs. Heap's of semi hubs set up oil/grease combo.

Scott

bannana
27-10-2013, 07:05 PM
I got my trailer built over there by ezloader and had oil bath hubs fitted. I just pulled it all apart the other day to see how it was all going after over three years of constant use, high miles and zero maintenance to find the bearings in perfect condition, no oil lost and everything in tip top condition.......

They will probably fall apart now you have touched them Muddy!!!

Muddy Toes
27-10-2013, 07:18 PM
They will probably fall apart now you have touched them Muddy!!!


You know what Keith?

That thought did cross my mind before I touched them and it still plays on my mind now.......
You've done nothing for my confidence..........rsole

MEGA'bite
27-10-2013, 07:20 PM
Darren J, there is a better system than the oil bath, AIR TIGHT , I have them on my USA boat trailer and have had them for quite some time with zero problems. There are as stated air tight, rear seal runs on stainless sleeve with a bearing/ dust cap on the front with provisions for an air pump needle.
All you do is pack your bearings as normal and every time before you put the boat in the drink you pump air into each hub with a bike pump and the air pressure holds and keeps the water out. I have forgotten to pump a few times and still have had no water get in.
You can source them here but if you are bringing in a trailer/boat get a heap of seals from the US

MEGA'bite
27-10-2013, 07:22 PM
buy the way Darren I also have the grease nipple in the centre of the stub axle and it doesn't work like a bearing buddy works

Rip it up
27-10-2013, 07:40 PM
I am a huge believer of dura hubs in oil baths. But I have found their downfall.

I just got back from a 700km round trip to stanage bay. 220km of unsealed dirt roads. Towing my 14ft fibreglass single axle trailer behind a ford ranger with large mud Tyres. Found that 60kms into the dirt my drivers side durahub was missing in action thought nothing much of it. Been on for a while maybe just shaken off. Install on one spare dura hub I had with me. Cleaned all dust and install new Lucas heavy oil. Drive the 50kms into stanage watching the mirrors carefully.

Arrive safely at stanage.

Check over the trailer and notice that the fresh durahub has a few rather larger impact chips on the outside edge and was knocked out of square. Like my mud Tyres where flicking rocks backwards at the exposed dura hub. As the hubs sit 30mm proud of the Tyres edge.

Do a very clean repair at the accom. As I carry good selection of tools with me. Used blue gasket silicon to glue the dinted hub back in. Planning my trip home I thought I would get the same attack. So I created a cloth duct tape hub cap. Which worked for approx 70kms home. Same attack of the flying rock. A quick clean up didn't do much. Too much oil and dust on the wheel. So I jam more heavy oil into the gap. And take off. I get off the dirt and check. Temp ok. And when the wheel stops spinning oil would run out. So the charge was on to get to rocky without stopping. 80kms away. All good. Testament to the SKF Bearings. Survived the test. Pull up at BCF to pick up a new set of durahubs. Repaired in the carpark to a fresh install.

So long story short. Love oil filling bearings. If installed well on the seal surface they really work. I run them on two trailers at present and will continue to use them on any new trailers.

Use good quality oil. And keep away from flying rocks.

I am considering using a different modified cap instead of durahubs though. Maybe a standard metal cap with a tig welded thickener reinforced center. Tap a small 8mm bolt into center. Will lose the clear viewing window. But gain a smaller profile on the hub. I do believe the durahubs are too long.



Damo's dodgy boat building factory.

Darren J
27-10-2013, 10:47 PM
buy the way Darren I also have the grease nipple in the centre of the stub axle and it doesn't work like a bearing buddy works
Are they eliminator torsion axles by any chance, made by tie down in the us?I think the system with nipple in the centre is theirs. The grease is supposed to pump in around the inner bearing, I am told they work ok, well enough that risk of seals leaking with oil bath hubs is not worth the risk.

Thanks all for the replies.

stue2
28-10-2013, 07:20 AM
All systems rely on a good seal. Grease will warm and move. Oil will move better but none will last with a bad seal.
as we all know moisture is the killer.
Secret is a well packed bearing before hand and not overfilling hub with grease as this can put more presure on bearing seals. I like thw oil system but have had years of trouble free trailering with a standard old cap and seal kit with well packed bearings
Cheers
Stu

Gon Fishun
28-10-2013, 07:59 AM
Have a read of this. It might help ease the stress of worrying about wheel bearings.
What old school mechanics already new.

http://www.google.com/patents/US3913992

littlejim
28-10-2013, 04:19 PM
I found packing the ribs of the seal near the big inner bearing with grease extended the life of my bearings by about 3 years. Still do an annual check though.

cormorant
29-10-2013, 10:09 AM
I found packing the ribs of the seal near the big inner bearing with grease extended the life of my bearings by about 3 years. Still do an annual check though.

Hi

Not sure if you pull the hub off the axel when you " annual check" but I replace the cheap seal every time I pull it off as it is near impossible to tell if they have a weakness / problem. If your check is just seeing if grease is emulsified from water and not pulling it off the axel I'll pull my head in.

My checks are simple
- No grease spewed from inner seal
- visual check of seal and shaft / sleeve it is working on ( I use double lip seals not marine seals)
- Grease not emulsified, hardened or dirty on outer bearing.
- Jack up wheel and check for movement and spin for noise check.
- hand temp check after and during every tow. If it is hot I know I am headed for a problem.
- Keep away from seals with degreaser and also direct lancing with pressure washers



PS - Read the patent. Got a summary as they are trying to greate a grease reservoir that goes to oil under pressure or temp and somehow they reckon it feeds from the gallery to the bearing. Not sure if you were trying to make the point that close to the bearing the grease turns to oil and replenished teh lubrication on the bearing?