Just looking at my BG Synroshift II that I use in my manual transaxle, and the Bg co rep told me that it does have quite a bit of ZDDP in, but no moly. He told me that Moly tends to not do well in high temp applications, or in gear oils. Some engine oils and grease or chain lubes Moly is a great additive, but not the best for gears or manual transmissions. The reason I ask, I was looking at the LubroMoly for gears (transaxles) and was wondering if it was a good additive to use in my Aisin 6spd transaxle.
moly in manual transmission fluid?
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How many miles on the transmission, what year model etc... If the transmission did not come from the factory with moly additive, and if it's made it for many miles without moly I see nothing moly can do for the transmission... Lots of questions on moly the last week or so...
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The car and transmission have ~30k on it. I'm not sure if the original fluid has moly in or not. The original fluid is 75w-80 GL-3 Mitsu DiaQueen New Multi Gear Oil.All I know is that it is not a synthetic fluid. The BG SynchroShift II is a 75w80 GL-4 Pao fluid. It seems to be working very well in my transmission. Better than the Amsoil Manual Trans fluid that I had tried out before. The amosil was hard shifting/stiff when cold in my application. It is also a 75w90 if I can remember correctly. The BG fluid seems to work very well, it also seems to have cut down on some of the downshifting/coasting noise I noticed in 1st and 2nd gear.
I just got off the phone is the LM rep, and was pretty happy about how honest and open the guy was with his product. He basically told me to keep running the recommened fluid in my transaxle, and leave it. He said that my fluid works great, and though in some applications the Moly additive is bennificial, he said that in other applications it can almost cause the fluid to be too slippery and and change the way the transmission feels when engaging the synchros. However, in a towing application for a rear differential under load, the Moly gear additive has proven to work very well and would def use it, just not in a lsd.
So I am happy with that. I'm tired of getting tech people on the lline with answers like "yeah, our product is great, no problems using it anything. In fact, use it in everything" So far I've been happy with the Mos2 in my engine oil,and am happy that their rep told me I am totally fine without their gear additive. Good to see that there are still some honest people out there.
So I am happy with that. I'm tired of getting tech people on the lline with answers like "yeah, our product is great, no problems using it anything. In fact, use it in everything" So far I've been happy with the Mos2 in my engine oil,and am happy that their rep told me I am totally fine without their gear additive. Good to see that there are still some honest people out there.
Originally Posted By: Johnny248
I just got off the phone is the LM rep, and was pretty happy about how honest and open the guy was with his product. He basically told me to keep running the recommened fluid in my transaxle, and leave it. He said that my fluid works great, and though in some applications the Moly additive is bennificial, he said that in other applications it can almost cause the fluid to be too slippery and and change the way the transmission feels when engaging the synchros. However, in a towing application for a rear differential under load, the Moly gear additive has proven to work very well and would def use it, just not in a lsd.
So I am happy with that. I'm tired of getting tech people on the lline with answers like "yeah, our product is great, no problems using it anything. In fact, use it in everything" So far I've been happy with the Mos2 in my engine oil,and am happy that their rep told me I am totally fine without their gear additive. Good to see that there are still some honest people out there.
I was pleased when I contacted them as well. It is a good feeling dealing with sales reps selling good products, honestly, and not making false, off the wall claims. That makes using their product a lot easier.
I just got off the phone is the LM rep, and was pretty happy about how honest and open the guy was with his product. He basically told me to keep running the recommened fluid in my transaxle, and leave it. He said that my fluid works great, and though in some applications the Moly additive is bennificial, he said that in other applications it can almost cause the fluid to be too slippery and and change the way the transmission feels when engaging the synchros. However, in a towing application for a rear differential under load, the Moly gear additive has proven to work very well and would def use it, just not in a lsd.
So I am happy with that. I'm tired of getting tech people on the lline with answers like "yeah, our product is great, no problems using it anything. In fact, use it in everything" So far I've been happy with the Mos2 in my engine oil,and am happy that their rep told me I am totally fine without their gear additive. Good to see that there are still some honest people out there.
I was pleased when I contacted them as well. It is a good feeling dealing with sales reps selling good products, honestly, and not making false, off the wall claims. That makes using their product a lot easier.
I agree. I'll continue to use their Mos2 product until someone shows some proof that it is no good.
Don't add moly to a manual trans. The synchros will not 'bite', and it is VERY tough to remove later. It imbeds and impregnates the pores of the materials.
Moly would be great for gears and bearings, but NOT for the synchros.
Moly would be great for gears and bearings, but NOT for the synchros.
I once used a moly additive in a manual trans, it does exactly what these guys say it does to the syncros.
Originally Posted By: d00df00d
Originally Posted By: widman
Moly is usually good for differentials (sliding contacts) but not for rolling contacts or synchronizers.
Why is that? Just out of curiosity.
Several have already answered most of your question, but there is a general consensus that frequently the moly is so good at sliding that it keeps the roller bearings from rolling, they just slide, as do the sychronizers.
Originally Posted By: widman
Moly is usually good for differentials (sliding contacts) but not for rolling contacts or synchronizers.
Why is that? Just out of curiosity.
Several have already answered most of your question, but there is a general consensus that frequently the moly is so good at sliding that it keeps the roller bearings from rolling, they just slide, as do the sychronizers.
MolaKule
Staff member
Here is a White paper on MT fluids:
https://bobistheoilguy.com/forums/threads/synchromesh-manual-transmission-lubricants.93561/
One of the reasons not to use moly in an MT is that it competes with the chemistry of the special synchro friction modifier.
https://bobistheoilguy.com/forums/threads/synchromesh-manual-transmission-lubricants.93561/
One of the reasons not to use moly in an MT is that it competes with the chemistry of the special synchro friction modifier.
There also is a thread on this forum about a guy trying moly in the trans, and it would not shift.
Absolutely horrible results.
Absolutely horrible results.
Originally Posted By: mechtech2
There also is a thread on this forum about a guy trying moly in the trans, and it would not shift.
Absolutely horrible results.
In that case, then why do some old Honda manual transmissions (80s??) recommend 10w-30 or 10w-40 motor oil? Don't many OTC motor oils contain moly?
There also is a thread on this forum about a guy trying moly in the trans, and it would not shift.
Absolutely horrible results.
In that case, then why do some old Honda manual transmissions (80s??) recommend 10w-30 or 10w-40 motor oil? Don't many OTC motor oils contain moly?
Critic - Good question. But it is additional/supplemental moly additives which are shift quality killers.
The tiny amount in engine oil that was OK'd for some Honda trannys sometimes was not enough to cause slipping of the synchros.
And note that this was for only some trannys on a few cars many years ago. A very very small amount of cars were OK'd for motor oil. And we now know that this is not the best at all, for other reasons.
The tiny amount in engine oil that was OK'd for some Honda trannys sometimes was not enough to cause slipping of the synchros.
And note that this was for only some trannys on a few cars many years ago. A very very small amount of cars were OK'd for motor oil. And we now know that this is not the best at all, for other reasons.
I tried quite a bit of grease with moly in my trans on a n86 toy truck.I coulda swore it made it a lot smoother to shift.
Hello everybody,
I personally didn't experienced any problems with MOS2 additives in a manual tranny. I am currently running one with a 2 % solid content for more than a year and all I can say is that it engage much smoother ( it was rather harsh before ).
Soluble moly, I don't know .....
I personally didn't experienced any problems with MOS2 additives in a manual tranny. I am currently running one with a 2 % solid content for more than a year and all I can say is that it engage much smoother ( it was rather harsh before ).
Soluble moly, I don't know .....
I have used Moly with Amsoil ATF in my Tremec T56 for 4 years. My car has 500 rwhp. This is a street car, not a drag car, but I take it down the 1/4 mile once or twice a year. Never have had a problem. I always wait for the fluid to get up to operating temps before shifting it hard. I was concerned that I needed more torque handling capability, and recently had it torn down for a 31 spline main shaft upgrade. The transmission mechanic said that it looked great inside. Hardly any wear at all. We did a full rebuild anyway. I have never put slicks on the car, but I do run drag radials to keep it civil under power. Just my vote for Moly! I believe in it.
I would love to use moly in manual trannys! I have in the past.
It would be great for all sorts of things, EXCEPT the very important actual contact of the synchro faces.
You might get lucky with aggressive synchros, but it's not worth it if things go bad.
How can we tell in advance? We can't! And the moly is very tough to remove all the way. Take it apart and grind it off!?
It would be great for all sorts of things, EXCEPT the very important actual contact of the synchro faces.
You might get lucky with aggressive synchros, but it's not worth it if things go bad.
How can we tell in advance? We can't! And the moly is very tough to remove all the way. Take it apart and grind it off!?
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