Differential leak

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skysurfer

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It looks like my 14b/sf is weeping from the axle tube housings. From the wetness pattern it doesn't look like it's the cover. Some sort of manufacturing holes there but don't know what purpose they serve. Something to do with locking the axle tubes to the diff maybe. So what are my options for fixing this? I'm thinking silicone on the outside or JB weld on the inside but was wondering if anyone else has seen this problem.

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VAL

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I had similar issue with my axle once. It turned out to be the pinion seal. It was leaking, and while driving it around, the oil would run down and cover the entire bottom half of the diff cover. I thought it was the welds also.
 

skysurfer

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Hadn't considered that, but I just checked and front half of the diff is dry.
 

CSFJ

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Before you condemn the plug welds, it would certainly be cheap and easy enough to reseal the cover. I'm wondering if it's spreading the way it is from an air current/vacuum condition underneath the vehicle while moving?
 

skysurfer

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I agree. It's been raining too much to deal with this until today. It doesn't make sense that both plugs would fail but it sure looks like that's where the problem is. Going to clean/dry everything and go for a drive to get a fresh look. Hope it's just the cover.
 

SkinnyG

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I have the same issue, and on mine it IS the axle plug welds. I've tried silicone (probably want Ultra Black), but I will do JB Weld next.
 

RThiel

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Clean them up, grind them out a little and reweld them. You're not going to put enough heat into the differential to hurt anything since you're basically just capping them with a cover pass.
 

skysurfer

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I have the same issue, and on mine it IS the axle plug welds.
Confirmed. Drove 20 miles and thought I could see some weeping on the passenger side plug. Wiped it off and drove back, could easily see it when I got home. (and found out my new camera takes pretty good close-ups lol)

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So now I have to decide whether I want to try welding this myself or having it done. I have both mig and stick, but equally suck at both. I'm not even sure if the diff is cast steel or cast iron. I could spend some time researching what's necessary or just whip out the wallet and be done with it. There's a shop about 10 minutes away that builds rock crawlers and stuff, I had them weld a broken shock mount before because I was too chicken-**** to weld near the gas tank. I think they charged me $20 so I might just swallow my pride and have them do it.
 

skysurfer

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From everything I've read these plug welds are done with nickel, which might as well be powdered unicorn horn for all the luck I've had finding someone local that can re-weld them. I decided to try a home repair first and used a JB Weld type of epoxy to see if that fixes it.

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I'm a little concerned about the axle itself. I also read that leaking axle plugs can sometimes indicate the tubes are twisting in the differential. The good news is that type of failure usually is accompanied by leakage where the tube slides into the housing and I don't have that. The right way to fix this if the tubes are walking is to have someone run a short bead where the tubes slide in. I don't know if that could be done on an assembled axle or if I would have to tear it down. I'd still have to find a guy who works with nickel and I know welders don't work cheap. For what it would cost I would probably be better off finding a full floater at the junkyard and ditching the sf. For now, I'm just going to drive it and see if it was a minor thing and the epoxy did the trick.
 

crazy4offroad

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Make sure you find somebody who KNOWS how to weld cast iron the RIGHT way. Have to use a torch to dry out all the oil seepage, as well as heat up the cast to anywhere above 200F, and it has to stay up like that while being welded. Then it has to be cooled very gradually. Many people use heat blankets but you can also use the torch occasionally to bring the temperature down slow. If it cools down too fast the weld will crack. It's best to have a completely stripped down housing with no 3rd member or axleshafts in it. If they try to start in on it while there's still oil in it go ahead and go somewhere else, they don't know what they're doing. The 14 FF under my camo truck, someone tried to weld and all of them cracked and looks like ****. (And NO it was not me lol) I'm just too lazy to strip everything out of it and go through the trouble to do it right, for what little bit of oil is lost.
 

crazy4offroad

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This may be a good option too
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Camar068

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good to know, thx
 

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