Oil in the bearings: Opinions wanted.

[mistaken1]

Some time back I took the deuce to town and back (2 hours on the highway). When I went to drain the air tanks I found gear oil pooled on the inside passenger front rear wheel. The dreaded axle vent and quite possibly too much oil in the differential. I freed up the axle vent and with the exception of a couple of trips around the block I have sidelined the truck until I can check the bearings.

So today I tore into the hub. With the exception of one stubborn budd nut disassembly went well. You can see from the pictures there is clearly oil in the bearings. When I removed the outer seal I found nothing in the keyway but grease and oil. You can see in one picture part of a cork seal that was most definitely not in the keyway. Looking at the inside of the brake drum it appears there has probably been a small but steady leak going on for a while.

Anyhow the bearings look good, the races look good, the seals look good. Most of the brake pads are clean and still rough.

My plan is to thoroughly clean and roughen the few slick areas of the brake pads, to thoroughly clean the drum and hub, to grease the bearings and reassemble everything using the original parts with the exception of the lock washer (that will be new). I will include a new cork seal as well.

On to the opinion part, sound reasonable?

And yes I did get grease on the wife’s camera.

 

[doghead]

sound reasonable

Yes.

I like to use a bit of RTV on the new cork, to retain it and help seal.

 

[Motorcar]

Yupper good plan, cork plug and possibly a new seal. The photo looks like an original seal there, if oil is passing it because the rubber is old and not plyable any longer it could leak and you will be doing it again. The cork can come from ACE hardware, bottle corks cut to size and less than a buck. I had to do the same job on mine when I first got it and it's been fine since, going on two years now.

 

[mistaken1]

When I picked the truck up from GL I was told that it was driven from KC to Jeff City 6 months before I drove it back to KC. The belts are new, the radiator hoses are new. All of the rear brake bleeders looked new. After getting inside, the brake pads look new. The rubber on the seals is clean and pliable, they look identical to the new ones I previously purchased. It really looks like the brakes were redone just before it went to GL.

I do want to pull the other side to check it. I need more lock washers before I can pull the back set.

 

[nk14zp]

Yes.

I like yo use a bit of RTV on the new cork, to retain it and help seal.

 

[Danl]

Danl M915A1 case farm tractor

I'm going to be doing the same job' I cleared the vent and it seemed to stop leaking, but I haven't ran the truck far jest around home , where dose one get new lock washers

 

[patracy]

Just my .02. I use ultra gray RTV when dealing with anything diesel or gear oil related.

 

[cityslug]

Instead of cork I made one from a piece of rubber.

 

[mistaken1]

Everyone, thank you for your input. For the record I used cork.

The deed is mostly done. I want to replace one bolt on the axle (1/2"-13 x 1-3/4" grade 8 ).

My cheap bearing packer did not work as well as I would have liked but it did get a fair amount of grease into bearings, I finished them by hand.

Using the floor jack to carry the weight of the hub while removing and replacing made things easier.

 

[Odyssey M]

The Ultra grey RTV worked well for me too. I replaced all my axle vents with tubing running up to the air cleaner. I have a suspicion that my original leak came from an over-pressure issue.

 

[steve6x6x6]

Just my .02. I use ultra gray RTV when dealing with anything diesel or gear oil related.

I will be doing mine next, ultra gray is what i will be using on the keyway. My CTIS system was full of gear oil from a bad outer seal and no cork in the keyway.

 

[turbovr6jetta]

My ? Even though you are done and it probably will work just fine. How much is a new outter seal? I think i paid 6ish bucks. Seems worth it to me to just have it be new. The inner isn't too important as far as I see it however I had a few inner bearings that were stubbern and I used the seal to tap the bearing loose. It was a cheap tool and I was planning on replacing them anyway. And some of you have seen the hub removal tool I made already but I think its worth posting again. You can slide the hub right off wheel it out side clean it and wheel it right back and it slides right back on. No chance of damaging a race, completly effort free. If you dont have a tranny jack, you should go buy one. I think harbor freight has them cheep.

 

[73m819]

oil-bearings-opinions.

Well here is my ,
The REASON for the GREASE is for WATER OPERATIONS, water does not MIX well with grease if water gets into the hub, where water WILL MIX with gear oil and if left in the hub, will rust the bearing and everything else.

These rockwell axles were a everyday use axle when these trucks were designed, they were a WET HUB, ONLY the MILITARY used a grease hub for the above reason.

So what I am saying is I see no reason other then water operations for the grease hubs, a GOOD axle to hub gasket and a good rear hub seal (original design) would be ok, a wet hub WILL run a LOT cooler then a grease hub because grease HOLDS heat.

 

[mistaken1]

And some of you have seen the hub removal tool I made already but I think its worth posting again. You can slide the hub right off wheel it out side clean it and wheel it right back and it slides right back on. No chance of damaging a race, completly effort free. If you dont have a tranny jack, you should go buy one. I think harbor freight has them cheep.

Nice! I will do something like that. Thanks for the idea and photo!

 

[turbovr6jetta]

oil-bearings-opinions.

Well here is my ,
The REASON for the GREASE is for WATER OPERATIONS, water does not MIX well with grease if water gets into the hub, where water WILL MIX with gear oil and if left in the hub, will rust the bearing and everything else.

These rockwell axles were a everyday use axle when these trucks were designed, they were a WET HUB, ONLY the MILITARY used a grease hub for the above reason.

So what I am saying is I see no reason other then water operations for the grease hubs, a GOOD axle to hub gasket and a good rear hub seal (original design) would not be ok, a wet hub WILL run a LOT cooler then a grease hub because grease HOLDS heat.

I'm not quite sure what your trying to suggest here. It sounds like you want to not worry about the outter seal and let oil in as per "original design" but you said it would NOT be okay. Just a bit confused.

Either way I dont know ANYTHING about 16 spline rockwells but I cant see how the original design could have ever been an oil bath style. There is no way to keep enough oil in the hub to keep it properly lubricated (without seriously over filling your diff). A lot of oil works great to lubricate bearings. A little does not. And even worse a little oil will wash grease out of a packed bearing. Please do all in your power to not let oil into these specific axle bearings. Without a serious redesign it will not work out well.

I guess that now my 4 cents as well

 

[73m819]

I'm not quite sure what your trying to suggest here. It sounds like you want to not worry about the outter seal and let oil in as per "original design" but you said it would NOT be okay. Just a bit confused.

Either way I dont know ANYTHING about 16 spline rockwells but I cant see how the original design could have ever been an oil bath style. There is no way to keep enough oil in the hub to keep it properly lubricated (without seriously over filling your diff). A lot of oil works great to lubricate bearings. A little does not. And even worse a little oil will wash grease out of a packed bearing. Please do all in your power to not let oil into these specific axle bearings. Without a serious redesign it will not work out well.

I guess that now my 4 cents as well

Sorry, ment OK thanks for bring that up, fixed it,
The CIVI design is the same design as the MILITARY design (same axle) which was a WET HUB DESIGN, only DOES NOT have the OUTER seal that the MILITARY had for water operations. the hubs on a truck do not stay FULL to the top with oil (not a oil bath), but rather oil runs down the axle tube as the truck leans, turns ect., this is the WAY ALL floating axles work, from 1/2t pickups to OTR trucks, this is ONE reason the the rears need to be checked and kept FULL, when a hub is pulled for maintenance, the WHOLE rear does not drain, only what is in the hub (unless the axle is leaning down towards the removed hub, then a bit more of a mess) after the hub/hubs is/are reinstalled, the axle sitting level, the rear is checked/refilled. when the hub is reinstalled, a LIGHT pack of grease is used as install lube, this leaves as the truck works (leaning, going around curves, ect) and rear oil runs down the tube, this is why after hub/hubs work and the check and fill of gear oil, the truck is taken on a test run, besides looking to make sure things are ok, the rear can be RECHECKED and topped off if needed.

 

[turbovr6jetta]

You seem far more experianced than I. But I would be real nervous about leaving out the seal and oil bathing these bearings. It sure seems like the (very) small amount of oil that would be just sitting there, not flowing through, on a long straight stretch of highway might not be suffecient. How many people have done this? I would of loved to have done this if many people have done this and not had problems after many miles. I was suprised they werent oil bath when I looked into it. Why would they sell these outer seals? Oh because they are packed bearings. It was news to me. The fronts sure but the rears seamed odd.

 

[patracy]

The normal inner most seal won't retain oil by design. That's why they tend to leak so easily.

 

[turbovr6jetta]

I was just looking into this. It seems as if no one has actually found a way to keep oil in. I found a neat drawing of a way to do it. But so far nobody that has done it. I will keep searching.

 

[patracy]

steve6x6x6 has.