Axle Leaks

[jeffhuey1n]

Pretty sure this topic has been covered, but I'd like to get some additionaal expert opinions on a leak on the rear-rear axle. Black thick oil has begun slowly creeping down the inside of the rear inboard wheel on my '72 M35A2. I'm assuming it's the inner seal but I'd appreciate any opinions if you've seen this before. Looks too thick for brake fluid and sorry, no pictures.

Checked the TM, not much good with what I could find, not sure of the correct book though.

 

[gimpyrobb]

Well, now that a seal is leaking, no reason not to go in and inspect everything. Seals, bearings, brake pad condition, wheel cyl, and brake pad retention hardware.

 

[m16ty]

Guess it depends on how you look at it. If you have gear oil leaking out of an axle it's the seal (or keyway) next to the end of the axle. I'd call that the outer seal.

As Gimpy said, you might as well tear it all down and service the whole assembly. At the very least you need to replace the seal and re-pack the bearings.

 

[wsucougarx]

I second the motion on tearing it all down. I was a bit intimidated at the thought of tearing my truck down at first. However, upon doing so, I was amazed on how elementary everything is. Not a whole lot of pieces to deal with. Actually it was quite easy. The hardest part if any was trying to find enough rags to clean my hand when repacking the bearings.

 

[sandcobra164]

I agree, that was the hardest part the first time. After rounding up all the tools I'd need to do the job, I kept putting it off. Once I finally jumped into the axle, it was only about a 2 hour process from start to finish and much easier than I imagined. Everything is pretty heavy though. New seals can be found on Ebay as well as from plenty of people on this site. There are some seals out there that aren't made quite right and while they seal up fine, people on here report higher hub temps with them. I've got a pair like that and while that one hub does run a little warmer than the others, it's not so bad that I'll quit driving the truck.

 

[jeffhuey1n]

Thanks all. Your correct; once its gotta come apart, might as well check it all. Good side: get new parts. Not so good side: got to find a shop to do it. Any big truck shop should be able to tear it down and rebuild it, shouldn't they?

 

[cattlerepairman]

Thanks all. Your correct; once its gotta come apart, might as well check it all. Good side: get new parts. Not so good side: got to find a shop to do it. Any big truck shop should be able to tear it down and rebuild it, shouldn't they?

Jeffhuey, I definitely recommend to jump the cliff and give it a try yourself. It is not "hard" or "complicated", and the only special tool you need is a 3inch socket for the axle nut (for about $25). If you do not yet have a beefy axle stand and a jack, then you are asking for trouble any time you drive the truck (and would be unable to deal with a flat on the front axle).

There are excellent write-ups on the how-to on this site. If you work on a flat surface, preferably paved, you can even pull both wheels and the brake drum as one unit, using a pallet jack.

Any truck or tractor shop can probably do it, but bear in mind that they are not used to grease-lubed wheel bearings (anymore) and the important stuff, such as what the keyway is and why it needs to be properly sealed may not be evident to them. They are used to bearings that run in an oil bath provided by the differential. At the very least, you need to provide them with printed out pages from the applicable TM.

 

[jeffhuey1n]

Jeffhuey, I definitely recommend to jump the cliff and give it a try yourself. It is not "hard" or "complicated", and the only special tool you need is a 3inch socket for the axle nut (for about $25). If you do not yet have a beefy axle stand and a jack, then you are asking for trouble any time you drive the truck (and would be unable to deal with a flat on the front axle).

Not a matter of desire. I would love to tear into those axels, if for no other reason than to see how it's put together. Unfortunately, both wrists were crunched in an accident. 7 surgeries later, I can drive the deuce, just can't do any of the "hard" work (is it really work if it's fun?). Once I find a shop, I'll definetely use your advice and give them a copy of the TM. Which TM details that perticular section?

 

[cattlerepairman]

I am sorry for your injuries, but glad that you can drive and enjoy your truck. You may want to look at the TM 9-2320-209-20-3-2 and print chapters 14-8 14-9 and 14-10!

 

[jeffhuey1n]

Thank you! Greatly appreciated!

 

[gimpyrobb]

Its a shame you are so far away. We are getting ready to do some axle rebuilds out this way.

 

[Heavysteven]

I gear oil got on your pads i would replace them. Also, if your having someone do the work it would be worth the money to buy extra parts just in case.

Here is what i would buy
Seals
Locking ring between the two nuts
extra lock nut
Pads
Wheel Cylinder or rebuild kit

 

[aspann]

Jeffhuey, I wish you had started this thread a few days earlier. I'm a newbee and I took my duce to a diesel mech. I ask him if he had ever worked on a duce, he said they were nuts and bolts like the rest of them. My right rear hub was warm to the touch and the others were cool. I had the seals and wanted him to check the bearings. He went into it and pulled the bearings and said they looked fine. I saw him when hewas looking at one bearing, it had a glob of grease on it about the size of a golf ball. He looked at it puzzled and then cleaned up the bearings. He replaced the bearings and seals. I asked him if he was going to pack the wheel bearings and he said they were in a oil bath. I drove it home,about 12 miles and the hub was still warm to touch.The next day I read your thread. Folks, what should I do now? Take it back to him and educate him or find another mech. I had told him about the cork for the keyway. He said he uses Permseal or something like that. I didn't see him put that on the keyway but did see him put it on the seal on the deal that is on the end of the axl.

 

[jeffhuey1n]

Gimpyrobb. wish you were closer too. Back before the accident, I rebuilt helicopters, no rotor head too small. Now, intense frustration that a simple bearing job has to go to a shop. Thanks for the advice Heavysteven, I'll put those on the list. aspann, from my experience with aircraft bearings, yours need replacing. Don't recommend going back to the original guy unless he'll make things right. You might get a little more time out of the bearings you've got but they'll need replacement, soon. I found a shop here in Cheyenne that I'm going to check out. I'll take a copy of the TM pages with me. If they listen, they'll probably do ok. If not, there's more shops.

 

[aspann]

Jeff, thanks for the reply, but I have already contacted the mech. and explanied that it wasn't an oil bath bearing. He says he understands now. He's going to do it over next week.
By the way, were you ever at FT. Rucker? I spent over 37 years there in avionics.

 

[jeffhuey1n]

No, closest I ever made it to Rucker was flying over it on the way to CCAD. When were you at Rucker? The one time I saw it the place was covered in our old H-3's. Something about a project to make Hinds, or something like that. My time was spent all over in both the Marines and the Air Force. H-53's, H-3's, H-1's and H-60's

 

[jwaller]

Jeff, thanks for the reply, but I have already contacted the mech. and explanied that it wasn't an oil bath bearing. He says he understands now. He's going to do it over next week.
By the way, were you ever at FT. Rucker? I spent over 37 years there in avionics.

be very careful taking it back. you might have gotten lucky driving it home to not torch a bearing running it dry like that but going back you may not be so lucky.

you can put cork or permaseal in the keyway, either is fine as long as it seals up.

 

[clinto]

Jeffhuey, I wish you had started this thread a few days earlier. I'm a newbee and I took my duce to a diesel mech. I ask him if he had ever worked on a duce, he said they were nuts and bolts like the rest of them. My right rear hub was warm to the touch and the others were cool. I had the seals and wanted him to check the bearings. He went into it and pulled the bearings and said they looked fine. I saw him when hewas looking at one bearing, it had a glob of grease on it about the size of a golf ball. He looked at it puzzled and then cleaned up the bearings. He replaced the bearings and seals. I asked him if he was going to pack the wheel bearings and he said they were in a oil bath. I drove it home,about 12 miles and the hub was still warm to touch.The next day I read your thread. Folks, what should I do now? Take it back to him and educate him or find another mech. I had told him about the cork for the keyway. He said he uses Permseal or something like that. I didn't see him put that on the keyway but did see him put it on the seal on the deal that is on the end of the axl.

Find another mechanic. Seriously.

The RTV/Permaseal/etc in the keyway is fine. I've never bothered to obtain/create a piece of cork. But I do always let them sit and cure for 24 hours.

 

[aspann]

Thanks all for the information.
Jeff, I was at Ft. Rucker from 1958 ($2 an hour) till 1999 when I retired. I was at Rucker before the Huey. Again, thanks to all for the good info. This is a great website.

 

[aspann]

Well, a friend and I are going to tackle redoing the seals in the rear axle. We will have to take off one tire at the time as we can't handle both at the same time. I have the seals and the cork for the keyway. I have been looking for the -20 TM to use. There is a guy on SS that says he has tons of TM's and I pulled up his site but couldn't find the correct TM. I think we can do it but not sure about adjusting those adjustment nuts. Could someone give us a heads-up on that. Maybe even sending the pages of the TM that covers that. I tried to download the TM off of SS sources, but it wouldn't download. Tried several times. Would be greatful for any help. Also, the grease we have is G403, GAA, 9150-01-190-0907,Mil G 10924c. Would this work?
Thanks