Oil in the bearings: Opinions wanted.

[73m819]

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

The seal is not a pressure seal, no pressure no leak for a good seal and seal surface, the rear seal is a standard design, take ANY floating axle hub apart, you will see the back seal. take a look at the (hate to say this) cucv's rear floating axle, you will NOTE no outer seal because it has a wet hub, the only thing different between a cucv floating axle and a deuce/5t floating axle is the SIZE, ANY seal will leak if the seal or the surface is crap, GREASE just helps hide a bad seal/surface and again a seal not designed for pressure WILL leak, A rear end is supposed to be pressure naturally. (NO PRESSURE)

 

[Danl]

Danl M915A1 case farm tractor

You are completely RIGHT that is why when these big riggs sit a while, the vent Often starts to plug with **** when the vent becomes completely plug, and one drives the truck the oil heat up and expands. now with no place for the expanded pressure to go it goes to the weekes piont the key way, Out comes the cork. Rtv makes the cork tighter, This is not really good, because now the seal is the weeker of the two. you will be fixing wheel seals next time. Now if you guys are not going to be makeing A beach Landing off of a U boat than you don't really need a check vent, try this pull the vent. Put a fitting that is pipe tread by hoes barb run a small plastic or rubber hose off of the barb end, Run it up above the pig than aim it down no water will enter and the thing will always be vented{ End of Thread}

 

[73m819]

just run a vent systen with ALL the vents with a cheap gas line filter on the other end of turned line, thes allows the rears, gear boxs BREATH without sucking dirt. almost ALL big rigs have a closed vent system.

 

[Danl]

Good move cheep briggs filter you are the man

 

[turbovr6jetta]

Most seals drive into the hub and the rubber seals on the axle housing I can't see this seal sealing anything besides some dust and stopping tons of water pouring in but couldn't possibly stop gear lube from dripping out slowly even without any pressure. Am I seriously messed up in my thinking?

 

[Danl]

Danl M915A1

this seal dose what you are thinking but with a pluged air vent on the pig you will have a presser builder up and the gear oil will run out real fast from that seal to stop this you have to vent presser better, and not let junk in when thing cool down and oil contracts

 

[73m819]

Most seals drive into the hub and the rubber seals on the axle housing I can't see this seal sealing anything besides some dust and stopping tons of water pouring in but couldn't possibly stop gear lube from dripping out slowly even without any pressure. Am I seriously messed up in my thinking?

Sorta yes, this is what the seals do, the seal is designed to KEEP out water and oil in, no different then ALL the gear boxs in/out put seals, gear boxs in machinery, gear box on your mower, a seal is a seal, all have the same job, you can get special seals like HIGH pressure seals, vacuum seals, extreme high speed seals, ect. they are ALL designed to keep something in, or to keep something out or both.

 

[mistaken1]

I did buy the fittings to run a vent system. Now would be as good a time as any to install.

 

[tuckered]

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.

They have tools for that now? WOW!

What is your civie source for GAA? I miss that stuff.

 

[DieselBob]

What is your civie source for GAA? I miss that stuff.

I get mine from here. Line 19.
Premium Genuine Issue U. S. Military Surplus. Including, United States Army, U.S. Navy and U.S.M.C. New Old Stock, Current Issue And Also Some Used.

 

[turbovr6jetta]

But on the inner seal of a deuce the part of the seal that "seals" to the axle portion is just a metal ring that presses onto the the axle. And its not really a press fit it in most terms would be considered a loose fit. And this is the part of the seal that would constantly be submerged with oil. I dont see how a flimsy thin metal ring with no pressure on it to seal it to the axle would prevent a small pool of even heavy weight oil from at least dripping a little. Back to an earlier question, have you or anyone else done this to a deuce? Testimonial means a lot to me. I have been wrong about many things where I either said there was no way in the wild world of sports something would work and it did, or I was absolutly positive something would work and had it just plain fail. I need a positive conclusion on this subject

 

[turbovr6jetta]

They have tools for that now? WOW!

What is your civie source for GAA? I miss that stuff.

Too bad the question wasnt "they have tools for that now, that actualy work?!?"

 

[mistaken1]

I used the red high temp bearing grease from the local farm store (mystic jt6).

And this:

 

[F18hornetM]

Ive worked on trucks all my life and this is the first truck I've seen "with" greased bearings. I understand why the military did it, but does anyone have a part number to replace the inner seal with a double lip seal?? A double lip seal, like modern trucks use, will keep oil in and water out. That way you could leave out the outter seal and silicone out of key way and no longer grease the bearings, they would be "wet hubs".
I do have books and books of seals that are sold by CR by dimension. inside , outside and type. I've just never tried looking it up with the dimensions needed.
I did my M35 and M813 with original seals, packed bearings etc, just wondered if anyone tried the double lip seals

 

[Vintage iron]

I work as a heavy truck mechanic and I have redone all of my hubs. The seals in our trucks are very similar to early Mack hub seals. The main reason that I think our axles leak is old seals, lack of maintenance and BAD axle vents. I am changing my axle vents to civi vents and changing my hubs to wet.

 

[DieselBob]

I wouldn't think the seal would have enough bore to seat in

 

[turbovr6jetta]

I used the red high temp bearing grease from the local farm store (mystic jt6).

And this:

I love high temp red grease. But I have never used a bearing packer that worked at least well enough to trust it. But like you said, finish them by hand. On a side note. I ran out of grease and had to buy a new tub at schucks or whatever they are now and the only brand they had was CRC. They make good brake cleaner. And it was Saturday night so I had no other option. When I got home and opened it I wasnt very happy with its color and density. Instead of being transparent red it was hazey and was like it was whipped, light and airy. I used it on both drums on the rear, rear axle and so far they are both running a little warmer than the rear, front axle. Maybe 10 degrees. I am suspicious of the grease. The rear, fronts run super cool so far and shortish trips and the rear has just a little heat... Must be chineese grease... I say make sure you buy good grease!

 

[turbovr6jetta]

I work as a heavy truck mechanic and I have redone all of my hubs. The seals in our trucks are very similar to early Mack hub seals. The main reason that I think our axles leak is old seals, lack of maintenance and BAD axle vents. I am changing my axle vents to civi vents and changing my hubs to wet.

Keep me posted on how it works out. I am very curious...

My theory is still that the inner seals leak as soon as enough oil leaks in through the outter seal and pools up in the bearings enough to leak out the back. But trust me I would be elated to be wrong.

 

[F18hornetM]

I work as a heavy truck mechanic and I have redone all of my hubs. The seals in our trucks are very similar to early Mack hub seals. The main reason that I think our axles leak is old seals, lack of maintenance and BAD axle vents. I am changing my axle vents to civi vents and changing my hubs to wet.

I agree with you. The 2 I had leaking were due to the cork gone out of key way. If you are changing yours to wet hubs, what seal number are you going to use?.
Of course what I use my trucks for [parades, car shows etc] the grease works just fine. But was thinking if I ever had another issue may change over to wet.

 

[F18hornetM]

I wouldn't think the seal would have enough bore to seat in

You might be right Bob. Most of the modern truck seals are approximately 1/2" thick or so where the seal meets the hub. So these may be a bit thin. Plus I'm not sure its really worth the effort to change. The grease does work fine with normal maintenance. But would be something to consider if the right part number came along.