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ARB Air Locker leaking oil

NorCal1971

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Jan 5, 2019
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10
Hi i have this ARB connected to Dana 60 (Rear). The rear is leaking oil through the valve filter at the pump. i believe up the air hose, but why? How do i fix it? in the picture you will see the little vent is missing, i added the vent but still leaks oil out the vent.

v2lP4Q.jpg

KSFYUT.jpg
 
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Broncobowsher

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First step, check the axle housing for a proper functioning vent. Not plugged up, breathing free. Just because it is present doesn't mean it isn't clogged.
 

Apogee

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If it's not a plugged vent causing higher than ambient pressure inside and differential and forcing diff oil past the o-ring (or x-ring on the newer ones) seals on the air ring, then you probably have failed the o/x-rings on the brass air ring where the hard line feeds air to the unit. Tear it down, swap the seals and it should be good to go.

For reference, what diff lube are you running? Brand, weight, type?
 

WILDHORSES

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Oil looks like it could use a swap too. Looks grey on my screen. NorCal? Near Sac? I have a guy I can put you in touch with if you don't do this kind of work yourself. PM if you would like info.

Jim
 
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NorCal1971

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Jan 5, 2019
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All, thank you for the advice. Of course working this week. This weekend I plan to look at your opinions. See what I can find. Apogee, you talk about seals, is this at the differential or at the pump? I recently bought the rig so I don’t know the oil specs. Jim, thanks I might ping you if I can’t figure it out. I’m in SF Bag area.


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tirewater

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If Jim's reference doesn't work, you could try Valley Hybrids in Stockton. Georg does a lot of Land Cruiser work (inc lockers) and is well respected in that community.
 

Broncobowsher

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The seals are in the differential. The piston that is moved by the air that mechanically locks the gears. It would be that seal.
 
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NorCal1971

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These seals, possible to point me to them? Like an ARB part number or URL? Maybe I can order before the weekend. Rear end is Dana 60.


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Broncobowsher

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I have never seen a part number for the seal. I think it is an ARB specific part. It's not the easiest to change. You are pulling the axles and taking the diff apart.
 

nvrstuk

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Broncobowsher

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A heads up, even if a seal fits one version of the locker, it may not fit yours. The lockers have been out for some time. ARB has a habit of quietly updating the design. There may be more then one possible seal for the same application. This is where you really need to talk with ARB.
 

nvrstuk

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That's exactly why I worded my post the way I did...no guarantee on whether the link was the correct part, and CALL ARB as their techs can help you.

Link was included just to show what the orings probably looked like...I'm installed many of these...

Good luck, CALL ARB
 

DirtDonk

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What's the dynamic at work here that allows the oil to pump back up the line all the way to the compressor? If it's diff oil, it's certainly not getting up there when the diff is activated because compressed air is pushing everything away from the part where it's leaking.

One way to see if the seal on the ARB is leaking would be to turn it on. Correct?
If it holds air for a certain amount of time, it's not leaking. Or it's leaking down so slightly that oil getting sucked back upstream is not likely.

Is there oil in the compressor maybe?

Paul
 

Hazegray

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Aug 10, 2004
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I second what Paul said: "Is there oil in the compressor maybe?"

Not knowing where the pump is located, that seems like an impossible task to have the oil travel upward to the pump...unless the pump broke a reed and is sucking/pushing air.
 

Broncobowsher

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Seal leaks can act as check valves. There might be enough of a lip to seal better on one direction over another. Little seal shrinkage. Add in pressure in the housing from a bad axle vent and heat as the axle warms up.

But activate the ARB and the air pressure will push the seal into place.

No oil in the compressor. They run dry.

The only way for that gear oil to be coming out of the solenoid is from a bad seal in the locker itself. No other way, has to be getting around the seal.
A bad breather might be putting pressure on the seal the opposite direction from what it is designed for.
 

Rox Crusher

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Dec 13, 2008
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As BB says, most likely seal failure in ARB collar or plugged vent in rear end.

If the vent is plugged, you may see it pushing gear oil out the pinion seal or the mating / mounting surface for the differential if it isn’t sealed well.
 

welndmn

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Nov 12, 2001
Messages
2,112
I've fixed a lot of ARBs over the years, the most common is a plugged vent line.
While it is common on a 9 inch, the seal housing have an o ring failure they with the rotation of carrier they end up acting like a pump and pump gear oil out the ARB, this is not common for a dana 60.
Pull the vent bolt out of the axle, blow it out with compressed air.
Disconnect both sides of the blue ARB line, and blow that out as well.
 
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NorCal1971

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Jan 5, 2019
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Welndmn and all,
Thanks. Welndmn, I understand from some of the comments to disconnect the air line on the differential side means taking the whole rear end apart?
Vent is for sure first thing I’ll go through.


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nvrstuk

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NorCal1971... just disconnect both ends of your ARB air supply line (compressor end and where the line enters your diff) and blow the line out to clear any oil out of it.

Most of the 1st page comments, especially the ones about the seals being the potential leakage spot were ONLY if the vent on the rear housing was clear and operating correctly.

Like previously mentioned, the 9" differential is more problemmatic with vents since the 9" the oil sometimes has a tendency to work it's way right out the vent line and keep siphoning it out..sometimes up to a quart... there's a fix for this but that isn't your problem right now (luckily). If you need to pull the 3rd member to do any repairs it might be something to look into.

Check the VENT first, clean out the air line between the diff and the compressor with compressed air, THEN activate your ARB and determine if you can hear air leaking, if the compressor cycles off and on within a minute or so, and if you eventually get more oil traveling back up the air line to your compressor... THEN it's probably the large o-ring seals that were discussed on the first page...but call ARB before ordering o-rings or ?

Good luck
 
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