what is friction modifer/limited slip additive?

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what is it chemically, or what ingredients are in friction modifier for gear oils?
 
i've not easily finding anywhere stating what friction modifier actually is made of.

i'm assuming they are all made of a similar type of oil and set of additives. is limited slip additive from ford, gm, royal purple, amsoil, redline all the same or are they completely different ?

http://en.wikipedia.org/wiki/Friction_modifier
all it says is glycerol mono-oleate is a "common" friction modifier. what are some others?
 
Originally Posted By: 1 FMF

i've not easily finding anywhere stating what friction modifier actually is made of.

i'm assuming they are all made of a similar type of oil and set of additives. is limited slip additive from ford, gm, royal purple, amsoil, redline all the same or are they completely different ?


The limited slip additives for differentials are not the same as PCMO friction modifers, is not the same as ATF friction modifiers, is not the same as MT, etc.

Limited slip additives are made of base oils and specialized chemistry, but most are similar in composition.


Quote:

http://en.wikipedia.org/wiki/Friction_modifier
all it says is glycerol mono-oleate is a "common" friction modifier. what are some others?


Wiki authors generally have no idea what it takes to make a lubricant.
 
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i was looking to find out what friction modifier is made of specifically for gear oils in differentials.

can you tell me what it is, or is it proprietary trade secret stuff that isn't disclosed ?

if i go to walmart or autozone and buy a cheap bottle of limited slip additive for gear oil for axle differentials, what's it made of?
 
Originally Posted By: Marco620
Probably no moly as that would cause less friction. Each company is probably be hush on what secret ingredient they use.



The ford friction modifier for gears is graphite. I'm almost positive.

Redline shockproof is made for gear sets. I know its loaded with moly and zddp. And it's an ester too so I'm assuming the competition is fierce for space.
Makes total sense to me the more I consider how an oil formulator has to consider what each element does and how each re-acts with another,then how does each compound re-act with other elements and compounds.
Certainly a balancing act. Knowing each elements assets and liabilities and using another to compensate for another compounds weaknesses.
It's an exacting science for sure.
I'm almost to the point that the only oil additives I will actually stock are ceratec,mos2 and motor oil saver.
 
Originally Posted By: 1 FMF
i was looking to find out what friction modifier is made of specifically for gear oils in differentials.

can you tell me what it is, or is it proprietary trade secret stuff that isn't disclosed ?

if i go to walmart or autozone and buy a cheap bottle of limited slip additive for gear oil for axle differentials, what's it made of?


The formulations and exact chemical constiuents are proprietary.

I am not sure what you mean by cheap. A limited number of blenders make most most of the LSA's you see on the shelves.
 
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by cheap i mean something off the shelf at autozone or advance auto that was a no name brand,

http://shop.advanceautoparts.com/p/k-w-c...hTerm=posi-trac

https://www.google.com/#q=limited+slip+friction+modifier&tbm=shop

if the links work, for rear axle differentials there is motorcraft stuff as cheap as $6.22 a bottle.
stuff from advance auto is less than $10.
from google shop it shows stuff from auburn gear for $15.
$8.10 http://www.amsoil.com/shop/by-product/gear-lube/slip-lock-gear-oil-additive/

so back to my very first question,
some people say use the ford additive it works best, others say get stuff from gm, and there's mopar, yukon, auburn, amsoil, redline, royal purple.... to name a few.

why would i choose one of those versus something off the shelf at walmart or whatever's at the local parts store?
 
Quote:
why would i choose one of those versus something off the shelf at walmart or whatever's at the local parts store?


If you are asking for a recommendation, I would choose whatever is local and the cheapest.
 
Originally Posted By: Corvette Owner
It used to be whale oil, but they changed it!


Yea, old timers think the whale oil is the only good stuff. Pretty shameful that they ever used that. It might be old man's tales.

I don't use limited slip additive. Why reduce the effectiveness of the system? I want it to grab hard when the right wheel starts to spin. Clutch popping sounds cool. Back end getting twitchy is also cool.
 
Originally Posted By: turtlevette
Originally Posted By: Corvette Owner
It used to be whale oil, but they changed it!


Yea, old timers think the whale oil is the only good stuff. Pretty shameful that they ever used that. It might be old man's tales.


Someday you will be an old F**rt too!
grin2.gif


There is a branch of chemistry called LIPIDS, with a subbranch called, marine-oil triglycerides. You might want to Google it.

The marine oil extracted for lubricants was Whale oil (which we have discussed here a least 12 times in this forum alone), or more accurately, Sperm Whale oil, from the spermiceli organ and which contains mostly liquid wax esters and some triglycerides.

This liquid Wax ester was primarily used in ATF fluids as friction modifiers because they were what was needed at the time and had quite good oxidation resistance.

Today, the liquid wax esters are synthesized by reacting euricic acid or other comparable acid(s) with specialized alcohols.

The euricic acid is derived by the fractioning of rapeseed feedstock oils.

I pity those poor rapeseed plants for having to endure this victimization.
frown.gif
I am sure the Gaiaon's would not approve of this process as well.


Quote:
I don't use limited slip additive. Why reduce the effectiveness of the system? I want it to grab hard when the right wheel starts to spin. Clutch popping sounds cool. Back end getting twitchy is also cool.


With your comprehensive mechanical background, I am sure you are aware of something called, "stick-slip," which is not to be confused with "slap-stick" comedy.
grin2.gif


This a sudden jump in relative sliding velocities which can cause excessive wear in Limited Slip Differential clutching mechanisms.

LSD additives reduce or eliminate the "stick-slip" action in order to reduce mechanism wear.

I always recommend adding 1/4 of a tube increments of LSD FM additive to the differential lube, and then testing doing figure eights to determine if stick-slip has been reduced or has disappeared.

I.E., use only enough LSD FM to make the stick-slip vanish.
 
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Originally Posted By: MolaKule

There is a branch of chemistry called LIPIDS, with a subbranch called, marine-oil triglycerides. You might want to Google it.

The marine oil extracted for lubricants was Whale oil (which we have discussed here a least 12 times in this forum alone), or more accurately, Sperm Whale oil, from the spermiceli organ and which contains mostly liquid wax esters and some triglycerides.

This liquid Wax ester was primarily used in ATF fluids as friction modifiers because they were what was needed at the time and had quite good oxidation resistance.

Today, the liquid wax esters are synthesized by reacting euricic acid or other comparable acid(s) with specialized alcohols.

The euricic acid is derived by the fractioning of rapeseed feedstock oils.

I pity those poor rapeseed plants for having to endure this victimization.
frown.gif
I am sure the Gaiaon's would not approve of this process as well.

So it is not good for use in engine oils ?
 
Originally Posted By: fpracha
MolaKule said:
So it is not good for use in engine oils ?


If you are speaking to the synthesized LWax esters, some types or variants may be used in engine oils as friction modifiers.

We must keep in mind that there different chemistry for different applications.
 
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Originally Posted By: MolaKule
Originally Posted By: fpracha
MolaKule said:
So it is not good for use in engine oils ?


If you are speaking to the synthesized LWax esters, some types or variants may be used in engine oils as friction modifiers.

We must keep in mind that there different chemistry for different applications.


Yes, like the type (hopefully) which are in the LubeGard Bio Tech Engine treatment (even though I know you are DEAD SET bagainst, and totally disapprove of ANY consumer added, 'extra-cirricular' engine oil additives
wink.gif
).

BTW; has ANYONE ever seen a limited slip friction modifier additive on the shelf at Sino Mart. I have not.
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I have changed oil on my F350 rear axle with LS probably 5 times in 200,000 miles. Don't know why but several LS additives I tried did not do the job. Only the Ford LS additive worked. It sure does stink!
 
Originally Posted By: Vstrom
I have changed oil on my F350 rear axle with LS probably 5 times in 200,000 miles. Don't know why but several LS additives I tried did not do the job. Only the Ford LS additive worked. It sure does stink!


Yes, I have also said on here MANY times that the Motorcraft XL-3 is the ONLY ls additive I will ever use, despite it's acrid/putrid stench.
wink.gif
 
This is a gen 1 model - so no Haldex or electrics - just replaced the trans and rebuilt the bevel gear (just a ring and pinion on a pto) Trans is a aw 42 that is new(factory rebuilt). Checked the rear end also.

Anyway, when all back together, real tight turns produced a binding/popping in the rear dif (there is a VC forward of the rear dif and that is new too) put some of the Ford FM in it and for the most part it has gone - only comes back if I hoon the car.

Question 1 - Should I try to eliminate the binding now that is is almost gone?

Bevel Gear - The thing with the 1st Gen awd volvos is the tight setup when the awd kicks in - almost instantly when the front wheels slip. This is great but it is really important to keep the tires within 3/32. Better to have smaller tire on back for all the reasons you would know about AWD. If tires are not correct you cook the VC, which stress the drive shaft which stresses the bevel gear - gear only holds a liter - it get hot under load, being under vented, pressure builds oils seeps out then you know the rest.

Question 2 - Volvo recommends the Toyota synth gear oil. In a straight line with good tires I would think that the load on the bevel gear would be modest - but on a long trip it would still heat up. Besides frequent intervals, is there some extreme uber killer gear oil that I could use? When I opened the gear it was like pudding inside - gears were ok though (shop said so)

Question 3 - I just put a new high flow head on - 1200 miles so far - would it be a good idea to go on and do an oil change now? Just in case or go the additional 2k more for the change?
 
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