Open differential gear oil, and Moly

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Seems like Gear oils have no Moly.

Seems like Moly in a differential oil would be the perfect place for the sliding deck of cards analogy of Moly's performance attributes.

I've got about 11K miles on some M1 75w-90 in a professionally rebuilt (new bearings) Chrysler 9.25. Open Differential, no LSD/ traction control/posi.
It seems to be a quiet Diff, but I'd really like to ensure longevity and a small fraction more MPG would also be appreciated.

Was considering a Lubro/LiquiMoly Mos2 gear oil Additive, Liqui Moly 2019.


Why do gear oils have no Moly?
What harm could there be in adding it to an open differential?

Seems as if Moly would be a great additive for an open differential gear oil, but perhaps there is something major I am missing.
 
Originally Posted By: wrcsixeight
Seems like Gear oils have no Moly.

Seems like Moly in a differential oil would be the perfect place for the sliding deck of cards analogy of Moly's performance attributes.

I've got about 11K miles on some M1 75w-90 in a professionally rebuilt (new bearings) Chrysler 9.25. Open Differential, no LSD/ traction control/posi.
It seems to be a quiet Diff, but I'd really like to ensure longevity and a small fraction more MPG would also be appreciated.

Was considering a Lubro/LiquiMoly Mos2 gear oil Additive, Liqui Moly 2019.


Why do gear oils have no Moly?
What harm could there be in adding it to an open differential?

Seems as if Moly would be a great additive for an open differential gear oil, but perhaps there is something major I am missing.
Clearly the makers of gear oil have ALL missed this.
 
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Originally Posted By: HerrStig
Clearly the makers of gear oil have ALL missed this.


Glad we got this expected response out of the way so quickly.

My question is Why, and more directed at Molekule and others similarly knowledgeable
 
I'm betting its due to the amount of clutching type posi-trac units out there and people not being able to read and using the wrong lubes. Moly is great stuff but you don't want it in an LSD diff!
 
I guess an old school axle with a Non LSD differential is just not what current gear oils are designed around, since gear oils also go into LSD Diffs and manual gearboxes too.

Seems like a gear oil designed solely around an open Diff, would have a different add pack since it does not worry about syncros or clutch plates.

The LiquiMoly Mos2 Gear oil Additive was only 9$. I ordered it.

I'll install it and watch a black Hole form around my Rear axle and swallow the earth whole.

Perhaps I'll order the Schaffer Hi moly gear oil in the future, but the M1 is too low a mileage to swap out now. I'd swapped the original fill 500 miles after installation by the driveline shop, as instructed.
 
Schaeffer's Oil Company has moly in many of their gear oils, in fact they pioneered the use of moly in gear oils and greases.

I think the reason most don't include moly is the possibility of moly interfering with the LSD additive chemistry in most gear oils.
 
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Thanks Mola, was hoping you'd chime in.

IF a gear oil were specifically formulated around an Open differential with no clutches or brass synchros, what EP/AW additives would you hope to see?

I know M1 is good stuff, but without clutches or Brass, it seems to my limited understanding, that something better could be installed to combat wear and friction to a higher degree.
 
Millers used to do a 'black moly' diff oil, but of course, it had big warnings about using it in synchro boxes and clutch packs without making sure it was compatible first.
 
What about moly and the roller bearings? I know the scale is much larger but aren't they basically the same thing as a needle bearing? Or does the larger size significantly reduce the risk of flat spotting?
 
A company selling gear oils with moly persuaded the plant manager at our generating station to have its super duper magic lube installed in a Philadelphia gearbox on one of our B&W MPS-89 coal pulverizers. . The engineering department installed a strip recorder on the motor to take before and after amp readings. No improvement whatsoever. Purchase price was repaid. I didn't want to pay for it in the first place. If the product was as good as the vendor said it was, I though the gear oil should be gratis and we would pay for it if the strip charts showed a real savings. This wasn't the first time snake oil had made its way through the front gate. That incident involved a member of our management team who showed up with one of those machines that is the subject of this post. If something is too good to be true, it probably isn't.
 
Schaeffer #267 automotive & industrial gear oil has MoS2 in it. Works great in my Eaton limited slip clutch-type differential for the last, oh, 100,000 miles or so. Yes, the clutches (to my surprise) still engage for the expected limited slip action after all these miles. I know this when turning on gravel or snow.
http://www.schaefferoil.com/cmss_files/attachmentlibrary/TD Sheets/267.pdf

Other Schaeffer gear oils have either MoS2 or oil-soluble moly compounds. http://www.schaefferoil.com/gear-oils-lubricants.html

Moly in needle bearings? Schaeffer #247 with MoS2 has been working fine in my Tundra's u-joints for the last 100,000 miles. I think any concern has been about poorly prepared MoS2.
 
On the '91 in my signature, I run Amsoil Severe Gear 75W110 in front Dana 60/NP205/rear Dana 70 with limited slip (PowrLok).

Would 1oz of Schaeffer's #132 per quart of diff fluid help my diffs/transfer case run more efficiently?

Originally Posted By: MolaKule
Schaeffer's Oil Company has moly in many of their gear oils, in fact they pioneered the use of moly in gear oils and greases.

I think the reason most don't include moly is the possibility of moly interfering with the LSD additive chemistry in most gear oils.
 
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Originally Posted By: MolaKule
Schaeffer's Oil Company has moly in many of their gear oils, in fact they pioneered the use of moly in gear oils and greases.

I think the reason most don't include moly is the possibility of moly interfering with the LSD additive chemistry in most gear oils.



Saw this had not been answered.

EP Gear oil chemistry is primarily a sulfur-Phosphorus chemistry. In some cases a Potassium Borate secondary EP additive found as in Chevron differential Lubes.

https://bobistheoilguy.com/forums/ubbthr...tion#Post729289
 
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Originally Posted By: ofelas
On the '91 in my signature, I run Amsoil Severe Gear 75W110 in front Dana 60/NP205/rear Dana 70 with limited slip (PowrLok).

Would 1oz of Schaeffer's #132 per quart of diff fluid help my diffs/transfer case run more efficiently?





#132 adds nothing to the S-P chemistry of a formulated GL-5 differential lube.
 
Got it; I'm assuming Amsoil has this S-P chemistry, but ordered whether the Penetro/ester in #132 would help protect diffs & transfer case gears.

Does #132 interfere with clutch packs?



Originally Posted By: MolaKule
Originally Posted By: ofelas
On the '91 in my signature, I run Amsoil Severe Gear 75W110 in front Dana 60/NP205/rear Dana 70 with limited slip (PowrLok).

Would 1oz of Schaeffer's #132 per quart of diff fluid help my diffs/transfer case run more efficiently?





#132 adds nothing to the S-P chemistry of a formulated GL-5 differential lube.
 
Originally Posted By: ofelas
Got it; I'm assuming Amsoil has this S-P chemistry, but ordered whether the Penetro/ester in #132 would help protect diffs & transfer case gears.

Does #132 interfere with clutch packs?





It could be as #132 has a multi-functional polymer that also acts as a friction modifier and has the potential to interfere with the Limited Slip Additive.

Amsoil's gear lubes do have the S-P EP chemistry as do most gear lubes.

As I said, #132 does nothing for a differential. It is only to be used in engines with problems.
 
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Right.

So - Schaeffer's quart bottles (5 gallon pail if I have to) , something with Moly simply because my OCD is taking over.

Like I said, I run Severe Gear in all diffs & gearboxes/Np205 transfer cases.

Do I go in for Schaeffers full synth #170 75w140 or partial synth 75w90 - 2937590 ?

Some off-road use, just occasional towing for my toys, PowrLoks, and part winters in -40 or so.

Will I see anything different from my current & time tested Amsoil Severe Gear?

Not looking to nit pick...just bored, and curious about Moly.
 
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