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Do you ROCOL your 80W90 in your rear drive?


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Yeah, the oil thread. lol. 

Ok. I have never seen anyone point to a Guzzi gear failure and say "I always used X brand oil in it". 
I have no idea what sort of testing regime Guzzi uses, or ever used in the past. So really I (we) are left to their recommendations and our own research and the anecdotal experience of others. 
My own research went so far down the rabbit hole that I spent a couple days researching industrial lubricants, separate from 'automotive' lubricants. Industrial gears come in every conceivable design and purpose, and are lubricated by everything from pressure to sprayed to bathed. Typically, industrial gears are loaded to their design intent far more often than automotive gears, so the demand on lubricants is higher. The short end of the long story is that I've chosen Chevron Delo ESI 75-140 for all my non-friction gears, whether straight or hypoid. In the 'Sport's straight-cut gearbox, there was a surprising reduction in noise over RedLine heavy shockproof, and a notable but unmeasured reduction in bevel drive temperature. The one consideration that I have not yet seen is the warning against water contamination and subsequent acidic corrosion. My vents are well-attended and I'll simply change the lube every season or two, this lube is not available in any local stores here but is not on the high end of expensive boutique oils to order. Does it matter? I don't know, I went 10,000 miles on RedLine heavy and came home with only about 100cc in the box after blowing it all out the vent with no damage to the gears, so not it my case. Would it matter with a loaded sidecar running the freeway at the speed limit? Who can say? Guzzi, BMW, Honda, Kawi- they all have different recommended lubes, and none of them are famous for drive gear failures. I think it's generally overthunk.

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17 hours ago, p6x said:

..MS for just the final drive? and why only the final drive and not the gearbox?

Because there is a lot more shearing pressure on the crown and pinion gear in the final drive than on the "normal" gears in the gearbox.


Also, I read somewhere recently that MOS2 can be prone to clumping if it is in somewhere where it is not needed, but I'm not at all sure of the details there.

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On 8/17/2023 at 3:57 PM, audiomick said:

Also, I read somewhere recently that MOS2 can be prone to clumping if it is in somewhere where it is not needed, but I'm not at all sure of the details there.

I'll let y'all know the next time I change the r. drive oil on my '72 Eldo....it has a removable sump, a good place for 20cc's of liquid moly to coagulate.:D

8/29/23 Update:  I removed the sump from the Eldo to change the oil.  I didn't see clumping but it appears that the heavier liquid moly (than 80w-90 gear oil) settles out to the lowest point when static.  


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This morning I added 20ml of the precious Liqui Moly MoS2 Anti-Friction for gears;

I quote:



Concentrated "moly" treatment for manual transmissions, transaxles, rear axles.

Reduces gear noise and whine. smoothens shifting.

Protect gears from pitting, scuffing, binding, overloading.

Reduces friction and wear. Add to gear lube-oil.


Content details:

Stabilized solid lubricant concentrate suspended in mineral oil. Thanks to its high MoS2 content and special additives, it is suitable for all manual motor vehicle transmissions and differentials without limited slip function.

Application: Miscible with most commercially available oils.

After a quick test drive, I can affirm:

-There is no more gear noise, and the gears shift very smoothly. That's even more incredible because I did not use the magic ingredient in the gear box.

Prior to this topic, I scrubbed the net, and found one Guzzi forum where this Molybdenum Sulfide requirement was discussed. As here, most of the owners never used the additive and never had any issue; including one who proudly quoted more than 100,000 miles done.

In any case, I will be laughing out loud from my grave, when my final transmission will reach 500,000 miles, going strong in the hands of its new owner!!!

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You can purchase moly from Harpers.  It's a real mess and whatever it gets on, will never come off.    In fact, I have to wonder once you pour it in, if it ever comes out?  I'd be interested in that Motul gear oil premix. 

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