Moly Grease for Dana/Spicer U Joints?

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I'm replacing all four universal joints (both driveshafts) on my Pajero/Montero, and bought Spicer branded replacements. Although I tried to source non-greaseable replacements, they are not available for this particular application.

I keep two grease guns; one with Motorcraft XG-1-E1 (moly) for chassis components like ball joints, pitman/idler arms, etc. and the other with Motorcraft XG-11 (non-moly) primarily for wheel bearings. The 14 oz. tubes are pretty hard to come by here, and outside of the Ford dealer, the only place that carries them is Ace Hardware under the STA-LUBE (CRC) brand. But even then, the range available is pretty limited.

The owners manual only specifies NLGI 2 for the factory units, and I often used moly grease in it. Looking at Spicer's video, I notice they are using a red grease, like Mobil 1 Synthetic:



Would it be safe to assume they do not want moly grease used in their U joints? Is Spicer Ultra-Premium Synthetic Grease red in color?
 
Would it be safe to assume they do not want moly grease used in their U joints? Is Spicer Ultra-Premium Synthetic Grease red in color?

The "color" is whatever that particular OEM decided on based on whatever they used to decide it with. Color is not a standard or "official" anything. ( you can have greases and oils dyed to fit a plant or companies lube strategy if you want to pay for it)

Moly grease would be a good choice for this application
 
I'm replacing all four universal joints (both driveshafts) on my Pajero/Montero, and bought Spicer branded replacements. Although I tried to source non-greaseable replacements, they are not available for this particular application.

I keep two grease guns; one with Motorcraft XG-1-E1 (moly) for chassis components like ball joints, pitman/idler arms, etc. and the other with Motorcraft XG-11 (non-moly) primarily for wheel bearings. The 14 oz. tubes are pretty hard to come by here, and outside of the Ford dealer, the only place that carries them is Ace Hardware under the STA-LUBE (CRC) brand. But even then, the range available is pretty limited.

The owners manual only specifies NLGI 2 for the factory units, and I often used moly grease in it. Looking at Spicer's video, I notice they are using a red grease, like Mobil 1 Synthetic:



Would it be safe to assume they do not want moly grease used in their U joints? Is Spicer Ultra-Premium Synthetic Grease red in color?


I have been using this Schaeffer's 219 more and more especially in parts that the use of moly comes into questions, U joints and plunge CV joints are just two.
After talking to them (not not girl on the desk answering the phones) they claim the moly is totally compatible with needle bearing types and one of their best greases. It is holding up well in one application that destroyed the OE grease and subsequently the needle roller bearings in a short time. Use the non moly Motorcraft for now and I will send you some of this over next time.


I deal with this outfit a lot for custom shafts and balancing, they use and recommend Mobil 1 synthetic (the red one) but say the 219 should work well.

 
Moly grease isn't the best for u-joints.

This is Spicer approved, and looks like the grease in the video.

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http://docs.mystiklubes.com/msds_pi/M20026.pdf
 
Would it be safe to assume they do not want moly grease used in their U joints?

No, but like most things, the proper answer is conditional and often misinformation and simply wrong information gets repeated enough to where it becomes the accepted "truth" then people don't ( or don't want to) understand or accept the facts because it upsets their worldview.

In general terms MoS2 is more an high loading pressure type anti wearing agent than a true lubricant and it work by coating.

Weaker concentrations are usually fine for most GP bearings but abnormal vibration signals can show up inn higher concentrations. It "works" but not really the best recommended for anti-friction bearings.

U-joint is a little different hybrid. Its usually a needle bearing (anti friction) but its lubrication regime is boundary because the needles never turn one complete revolution during the service lift ( the shaft turns but the bearings just move back and forth) unlike a true rolling element bearing.

It runs and wears more like gear teeth hitting over the life cycle.

That's why you would most likely benefit in that application.
 
On the other hand GKN specifically specifies no moly grease on their plunge type joints because of the needle bearings that do not make a full rotation either in normal use. Ford uses moly 3% in their wheel bearings other companies do not.
I have no idea but when a grease is available with a different type of moly is available and the manufacturer claims it is okay for needle bearings that is what I am going with.
 
On the other hand GKN specifically specifies no moly grease on their plunge type joints because of the needle bearings that do not make a full rotation either in normal use. Ford uses moly 3% in their wheel bearings other companies do not.
I have no idea but when a grease is available with a different type of moly is available and the manufacturer claims it is okay for needle bearings that is what I am going with.

LOL, I run into these contradictions all of the time (If all the answers were linear and simple, no one would call us)

They are not contradictions as much as often they are simply "statements" ( with no data support at all) all the way to "theres a reason but its protected IP). Some are even "conditional" but a company will issue a blanket statement but put a comment like "contact "X" engineering about your specific application" in very small print.

Personally myself when investigating these things to develop standardized lube selection and practices I have seen....

An OEM simple took the recommendation of a lube manufacturer with no incumbent research

Some OEM's have a performance or other characteristic in their design that requires/prohibits a certain thing ( this is probably the most important one)

Some do no engineering whatsoever ( mostly clones) and just copy whatever others do

Some say "maybe' and call us

To your point, if an OEM specifically calls out something ( either way)- its wise and best to go by that because its there for a reason.
 
I have been using this Schaeffer's 219 more and more especially in parts that the use of moly comes into questions, U joints and plunge CV joints are just two.
After talking to them (not not girl on the desk answering the phones) they claim the moly is totally compatible with needle bearing types and one of their best greases. It is holding up well in one application that destroyed the OE grease and subsequently the needle roller bearings in a short time. Use the non moly Motorcraft for now and I will send you some of this over next time.


I deal with this outfit a lot for custom shafts and balancing, they use and recommend Mobil 1 synthetic (the red one) but say the 219 should work well.

I am using the 219 in everything now even repacking wheel bearings. The pins on some of my equipment now only take 1 pump to see grease where they used to take 2-3. I switched from JT6 High temp with moly. I’m running everything from farm and hay equipment to a dump truck and semi. Also using it in a Cat track loader too.
 
I am using the 219 in everything now even repacking wheel bearings. The pins on some of my equipment now only take 1 pump to see grease where they used to take 2-3. I switched from JT6 High temp with moly. I’m running everything from farm and hay equipment to a dump truck and semi. Also using it in a Cat track loader too.

The 219 seems to be a great grease for many applications. Time will tell how it holds up long term in suspension parts that get neglected, the 5% moly in the 238 seems to hang in there a long time.
 
Do not use moly grease in high speed needle bearings like U joints. It'll work, just not well. You want the needles to roll freely not slide on one contact point. Moly grease on the other hand is ideal for parts that are supposed to slide on one contact point like a BJ.
I know that moly in high speed bearings especially needle bearings has long since been a taboo subject here and elsewhere however I have never had a u joint fail due to it. ABN described above what I’ve always felt about it. With most normal pinion angles your bearings won’t make a full rotation, they will shift back and forth most of the time. I feel that a moly grease is fine in this application. Schaeffer also claims that the “synthesized moly” in the 219 is fine in high speed bearings. They even list electric motor bearings on the tube.
 
I would try to avoid using grease containing moly if you can.

Dana recommends lubrication with Spicer ultra-premium synthetic grease, Chevron Ultra-Duty EP-2, or a compatible lithium-based grease meeting NLGI Grade 2 and ASTM D4950 LB specifications. Spicer ultra-premium synthetic grease is compatible with all NLGI-2 greases
 
I know that moly in high speed bearings especially needle bearings has long since been a taboo subject here and elsewhere however I have never had a u joint fail due to it. ABN described above what I’ve always felt about it. With most normal pinion angles your bearings won’t make a full rotation, they will shift back and forth most of the time. I feel that a moly grease is fine in this application. Schaeffer also claims that the “synthesized moly” in the 219 is fine in high speed bearings. They even list electric motor bearings on the tube.
You can often get away with using a sub-optimal grease on something, but all the various ones exist for reasons. Whether the needles make full rotation or not, moly can only decrease their rotation, is no benefit in this application unless the bearings are worn out and the needles are skidding.

It is often the case that a manufacturer suggests their product is good for as many different applications as possible, but then the question is whether good = best, considering grease w/o moly isn't exactly hard to come by or expensive.
 
I’ve used moly 5% or less for approximately 30 years in my 1990 dodge w250 4x4 diesel.
This vehicle has been loaded far beyond its legal capacity and the rear driveshaft unjoints have never been replaced and currently have 250k + miles on them.
In an application that is always loaded the needles will always roll not slide.
I’m aware of the pros/cons of moly grease application and have not experienced any issues.
I continue to use moly to this day.
The pros for me is reduced steering effort on a truck with a solid front axle with king pins. The upper king pin is engineered plastic and the lower load bearing king pin is a tapered roller bearing which have never been replaced and I live in the rust belt.
I have equipment that requires moly (loader pins)
I want 1 grease for everything and moly works fine in every application I have. 90cummins
 
I use a #2 grease on my spicer u-joints. Mobil1/Valvoline Synthetic, etc… 145,000 miles now… they don’t seem very picky as long as you actually grease them.
 
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