Rear axle continues to leak

[two.fiveM35]

My left rear axle continues to leak and wash all the bearing grease out. This has been an issue since I got the truck. It was a fresh military rebuild when I picked it up and the axle was dry. It started to leak after about 100 miles, and since my mechanic has replaced the axle seal 2 times and it continues to leak after about <100 miles. We have both checked the axle vent and it seems fine. I also don't think it is an issue with my mechanic because he has worked on these in the service. I don't think the axle shaft is bent because I'm not seeing any wobble when I drive. I am planning to jack up the rear end and look at the axle as soldier "B" puts it in gear.

Any ideas on what the problem could be???? Could the axle shaft be machined to small, not allowing the seal to seat correctly?

 

[rlwm211]

If there is not a piece of cork in the keyway this can happen. Some folks use RTV but Cork works better and once in place does the job and it can be removed carefully and reinstalled when you need to service the bearings or seals.

 

[doghead]

Remove the vent after a ride, and see if there is any pressure at all.

Or, just leave it off for a trip.

What brand/source are you buying for replacement seals?

Correct bearing preload is important.

Is the sealing surface of the hub damaged?

Is it the inner or outer seal that keeps leaking?


Every former GI was a mechanic... or a driver, or a .....

 

[two.fiveM35]

It's the inner seal that he has replaced. He works for his dad at their auto repair shop and has been servicing another guys deuce for many year now. although I wouldn't mind a second set of eyes to look at it. Anybody know of any shops in the HOUSTON area??

 

[F18hornetM]

Mine was leaking at the cork in the key way. Seal looked pefect. Didnt replace it. cleaned it all up, packed bearings, used silicone, [good silicone] and so far good.
He may be a mechanic, but all the other trucks I've worked on dont have an inner and outter seal. He may be the same way. The inner seal on these trucks is more like a dust seal..to keep dirt out, not oil in. The outter seal and cork are the only thing keeps oil from the bearings.
I have wondered why they used this design, could be just an old design as modern trucks have a double lip inner seal, and oiled, not greased bearings

 

[rlwm211]

You could pull the axle and take a small plastic stick or tube from a spray lube can and slide up into the keyway. If it does not stop at the bearing there is no cork in there. The cork, or silicone needs to be right up against the tab on the seal.

Most all big trucks use oil bath lubrication for the wheel bearings. The deuce use grease for the bearings. Unless you know to put the cork in the keyway you would not bother on reassembly. If I were you, my first question to my mechanic is about this cork. He ought to remember since he has done it twice.

Owning one of these trucks comes with a learning curve, free of charge I might add. Until You actually get some of the maintenance on these done, either by yourself or by a mechanic, you really are uninformed as to the needs of such beasts.

You think the keyway thing is fun, wait until you have to replace and repair the brakes.

I am quite sure it is something simple as these trucks are simple.

Keep on posting how things are going as things develop

 

[F18hornetM]

I put a small amount of silicone against the tab before threading on nut, then after nut installed another small dab..doesnt take a lot. Then didnt drive truck down the road for a day or so to let cure well.
Ive worked on trucks for 30 years and had never seen seal this type on a truck. I have seen it on some old pole trailers though. But since the trailers didnt have oil, cork wasnt needed in key way..

 

[Ridgerunner]

I use RVT silly-cone, in the spindle hub keyways on my deuce and never had one leak. If that's your leak sorce, it's an easy fix. Just make sure that it's clean and completely oil/grease free, before applying the RVT.

 

[two.fiveM35]

Thanks guys for all the tips. I'll keep you in formed. Ive been meaning to join the museum in Houston, I may go by there and see if they have any recommendation on mechanics. I live in a subdivision, and if I work on the truck here the subdivision Nazi will write me up.

 

[rlwm211]

Actually, I am mistaken. Must be age or something. The cork goes under the bearing race and up against the seal tab. There is no way to check it without taking the locknut, washer and inner nut off.

Sorry for the mix up......

 

[Heavysteven]

I use blue RTV and a material called viton instead of cork.

 

[Heavysteven]

A photo of the viton piece in the keyway.

 

[rlwm211]

I have a chevy cork valve cover gasket that I cut pieces out of if I need to for replacement of these important seals. Viton is good too. The nice thing about cork is that is swells slightly when it encounters the oil ahd that helps ensure it is a good seal and nice and tight.

 

[73m819]

The reason for the grease instead of oil (wet bearings) is the underwater fording CAPABILTY, if you get water in a wet bearing, it will wash the oil out, not so on a grease packed bearing, after the fording as soon a possible the truck needs to be PMed, but can be run till then, water in a wet bearing instead of oil WILL mean a very short bearing life

 

[F18hornetM]

ahhh, thanks 73m819, that makes sense. Grease will continue to function when submerged to a point.
But a double lip seal will keep water out and oil in. For the most part..but does make sense, esepcially with the material and design back then.

 

[kcollum]

I had a similar problem with rear left tandem. When I got the truck I cleaned all the axle vents,then a few weeks later the wheel seal started leaking. So I tried the simple fix first and pulled out the axle vent. When I removed it there was a small rush of air or pressure being released from the axle, I took an air hose and blew out the vent, but it seamed a little had to blow by mouth. Took it apart and found the rubber cap that seals the vent was stuck on one side. So after freeing it up and re installing it no more leak and no pressure in the axle. Seeing how you have had replaced the seals twice it might be the vent.

Best,

Ken

 

[doghead]

Kcollum, that is very very common.

 

[two.fiveM35]

Thanks Ken, I'll look into that. I need to order something from Erik's Surplus and saw he had some new vents. I think I will add a couple to my order.

 

[two.fiveM35]

If it leaked out of the keyway, where would I see the oil? On the outer wheel? My oil is leaking onto the inside of the inner wheel.

 

[73m819]

instead of the vents, pull all 5, throw them wary, install hose barbs and lines, tee as needed, run the hose to the firewall, in this end install a cheap in line fuel filter to keep dust out, the housings can breath and no pressure build up

5 = 3 axles, 1 trans, 1 transfer