Best Grease for Yukon Extreme Hardcore U Joints

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I am getting ready to install a pair of Yukon Hardcore Extreme U Joints into some new Chrome Moly axle shafts in my Jeep TJ rock crawler and the U Joints don't have needle bearings, they use a 4140 steel cap that ride on the 4340 chrome moly body. Yukon recommends copper anti sieze for lubrication on the bearing caps. Is this a good idea? Is there something better for water resistance and extreme pressure? I currently use Lucas red and tacky in most of my applications. The U Joints have a flush fitting on each cap that is greased with a need grease fitting. I will only be having these engaged off road without any high speed driving.

 
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Those are different sounds like they're metal on metal with no bearings.

The anti-sieze recommendation makes me think they want pretty much all solids for the lube. I'd stick with the anti-sieze of maybe a moly paste.
 

Southpaw338rum

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Call Yukon and get their exact recommendation.
Yukon wants you to use a copper based anti sieze that is way over priced at over 50.00 for 4 oz. When the U joints cost 350.00 for a pair, I don't want to cheap out and make a mistake, but I am trying to figure out what will work for max life. The other odd part about these U Joints is that they use an o ring seal and Yukon says to grease the cap but don't force grease out of the o ring or it will be damaged. My thought is a high quality waterproof grease possibly with moly or just an extreme pressure like red n tacky.
 

Southpaw338rum

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Those are different sounds like they're metal on metal with no bearings.

The anti-sieze recommendation makes me think they want pretty much all solids for the lube. I'd stick with the anti-sieze of maybe a moly paste.
This is a steel on steel design with the cross being 4340 and the caps 4120 chrome moly. They want the cap to wear and not the cross.
 
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Yukon wants you to use a copper based anti sieze that is way over priced at over 50.00 for 4 oz. When the U joints cost 350.00 for a pair, I don't want to cheap out and make a mistake, but I am trying to figure out what will work for max life. The other odd part about these U Joints is that they use an o ring seal and Yukon says to grease the cap but don't force grease out of the o ring or it will be damaged. My thought is a high quality waterproof grease possibly with moly or just an extreme pressure like red n tacky.
Again use exactly what is recommended as you have purchased a specialty product. The U joints cost as you posted $350.00 per pair. I just read up on them.
 
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That's a strange recommendation from Yukon since anti-seize really isn't a lubricant.

Regular and Copper are lubes, don't worry!
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I have Yukon Super joints (not to be confused with the Saturday night Super joint) in my front axle. The joints should come with a small tube from Yukon, but if not, I have used Permatex without issue.

BTW, Dana 60 Superjoints are $500 +. The alternative would be RCV's, which run in the neighborhood of $3K for the shafts. Pretty awesome stuff though.
 
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I am getting ready to install a pair of Yukon Hardcore Extreme U Joints into some new Chrome Moly axle shafts in my Jeep TJ rock crawler

Those are 297's. Are you running a Dana 30 or Rubicon 44 (or possibly a transplanted Waggy 44)?

What size tires are you planning to run?
 

Southpaw338rum

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Regular and Copper are lubes, don't worry!
View attachment 137295 View attachment 137296

I have Yukon Super joints (not to be confused with the Saturday night Super joint) in my front axle. The joints should come with a small tube from Yukon, but if not, I have used Permatex without issue.

BTW, Dana 60 Superjoints are $500 +. The alternative would be RCV's, which run in the neighborhood of $3K for the shafts. Pretty awesome stuff though.
I probably would have ordered RCV's but when I checked last week the lead time was 16-20 weeks out and I don't have that much patience. I might want to hit Moab for Easter Jeep Safari and these shafts will be my primary shafts and my current chrome moly's will become spares. I went ahead and ordered some of the Yukon grease since I already had an order in for some other parts.
 

Southpaw338rum

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Those are 297's. Are you running a Dana 30 or Rubicon 44 (or possibly a transplanted Waggy 44)?

What size tires are you planning to run?
I have a Currie HP 9 inch up front with chrome moly shafts, warn free spin kit with 30 spline outers. I run 35x12.5x15 Mickey Thompson MTZ's, ARB's front and rear, atlas II TC, klune V doubler, 4.56 gears and a new Cummins R2.8 turbo diesel.
 

Southpaw338rum

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I ordered the Yukon grease and they don't give that stuff away. Almost 50.00 wholesale for 4 oz! The grease they spec out is a aircraft spec grade lube, not sure if that means anything or not. Probably the same stuff as listed above in Permatex copper antisieze. I used to use that stuff on high heat large base light bulbs to keep them from siezing to the fixtures.
 
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