Gear oil leak

[IronPig]

Does this look like evidence of a bad axle seal?

Both rear axles leak on the passenger side, fluid smells like gear oil. We did notice that all three axles were slightly low, and topped them off to the fill plug.

1. Could they have been overfilled?
2. Are the axles pressurized, and if so could a clogged breather cause this?
or
3. just a bad axle seal?

Thanks!

 

[southdave]

maybe brakes, check the fiuld, also what dose it smell cant mistake gear oil the smell reminds me of pusulated wound

 

[southdave]

sorry my bad, forgot what you said, over pres. I would guess yes

 

[FMJ]

Bad inner seal, also check the keyway seal, and the outter seal. When the keyway/outer seal leaks, it allows the gear lube into the hub, washes out the grease and then leaks past the inner seal. The bearings in the axles are packed with grease only, and should not be getting gear lube.

 

[bottleworks]

Could be a bad seal or the axle breather could be clogged and forcing the lube past the seal. You have to pull that hub off now anyway. Just be sure your breather is clear once you finish the repair.

 

[Recovry4x4]

The inner seal is only designed to keep junk out and grease in. These seals were never designed to retain gear oil so I'd suspect the outer seal or more than likely the keyway gasket. Either one or both of these have failed or the breather has failed and forced the gear oil past the outer seals and subsequenty the inner seal. More often than not, the inner seal is still good. No way for gear oil to get to that seal unless the breather or outers have failed. If an inner seal fails, you should see wheel bearing grease oozing out. Just to clarify, the inner seal is on the spindle, the outer seal is right under the wheel bearing nuts.

 

[FormerNewMVGuy]

Also the proper oil level in the differential is 1/2 inch below the fill hole.

 

[clinto]

It's an easy job, there is a great writeup somewhere on the site about it. OPCOM also has a great writeup on his website, hopefully he will chime in.

 

[bigmike]

Re: RE: Gear oil leak

It's an easy job, there is a great writeup somewhere on the site about it. OPCOM also has a great writeup on his website, hopefully he will chime in.

Ditto.

OPCOM'S write up in in the tech article section.

 

[yellobronc]

RE: Re: RE: Gear oil leak

great info, I was wondering if oil was supposed to be between the bearings, I have lots of it and it didnt seem right. Now I know, does anyone have the napa number for the seals or do I need to go to OD iron now that I have it all taken apart?

 

[Floridianson]

Just a thought. The top pic shows well the two large nuts on the bottom of the backing plate. When you have the wheel off take the nuts off all the way and put anti-seize compound on the threads of stud and nut. These are for the major brake adj. and will help when you need to adj.

 

[yellobronc]

I was just in all 4 rear wheel ends and found in my Duece, there was very little wheel bearing grease in the bearings and all 4 wheels appeared to have the cavity between the seals filled to the height of the bearing races with gear oil. I have been told many semi truck setups use gear oil to lube the bearings. Is it possible that somebody made an effort to switch to gear oil to oil the wheel bearings on my truck?

I ended up sucking the oil out and repacking all my wheel bearings with grease and reassembing them without the gear oil in the bearings. I guess I can keep an eye on it and see if it happens again.

Is there something wrong in my truck that would affect all 4 axle ends?

 

[CanonNinja]

to temporarily hijack the thread... i have a leak like that on the front, although not near that bad, and only when the truck sits for a while... never have a leak in motion or more than maybe a 10th of that on the tire... same inner seal perhaps?

 

[Iyaayas184]

Yup it sure do

Looks just like mine when the axle seal went bad, fortunately it isn't real hard to fix.

Bob

 

[Floridianson]

CanonNinja; Sorry if yours is gear oil than no. Banshee has a good post with pics on front axle seal replacement.
Yellobronc; Did you put in new key way cork? The trucks I have worked on share oil with the diff. but the oil seal and bearing are installed in the hub.

 

[rsh253]

Ironpig,

Did you figure out what your leak was, and, if so, what was the fix?

I just bought my first M35, and as I was driving it home it developed the exact same leaks. Your photos could have been of my truck. Like yours, both wheels on the he passenger side rear wheels leaked. Anything you can tell me would be appreciated. Thanks.

-Russ