Friction Modifiers

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KW

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What are they and is an oil with them better than oils with out them? Big truck oils don't have them; bike oils don't have them. Do friction modifiers make a better oil or a sub-standard oil?
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Organic friction modifiers are used in gas engine oils to help them pass the "Sequence IVB", fuel efficiency test. This test is a requirement for SL and/or GF-3, gas engine oils and allows them to display the "starburst" that you also find in owners manuals for new vehicles.
This is an attempt to influence buying habits and get folks to use low viscosity, 5w-20/5w-30 oils in order to oprimize fuel efficiency.

Organic FM's typically improve fuel efficiency by 1%-2%, which is enough to pass this test - at least after 96 hours. What happens to these products after that is anybodies guess? ....This is the main reason why you see small amounts of moly and/or boron being used by many oil formulators. MoDTC is one of the more effective FM's out there and the Sequence IVB test happens to respond very well to it ....Organic friction modifiers didn't have much impact on the earlier API Sequence test to measure fuel efficiency, so you weren't seeing Moly and/or boron used several years ago, except in high end synthetics. Redline has used Moly for a number of years, and Amsoil has been using Borate esters since at least 1996, as they showed up in my early tests of the Series 2000 oils ....

Tooslick
Dixie Synthetics
 
Do these FMs give any measurable power on a dyno increases compared to an identical oil without FMs? Is it the FM capability of Redline that allows it to have an edge over M1 and others?
 
quote:

Originally posted by TooSlick:
Organic friction modifiers are used in gas engine oils to help them pass the "Sequence IVB", fuel efficiency test. This test is a requirement for SL and/or GF-3, gas engine oils and allows them to display the "starburst" that you also find in owners manuals for new vehicles.
This is an attempt to influence buying habits and get folks to use low viscosity, 5w-20/5w-30 oils in order to oprimize fuel efficiency.


I agree, but for one thing. I don't think the fuel efficiency test is required for SL. Check out any SL 10w40 or higher grade oil (or any grade of the so-called high mileage oils) and it will not have the starburst, nor will it have the words "Energy Conserving" in the API
donut. A 10w40 can't pass the test as the test oil a supplier has to beat is a 5w30 synthetic.
 
I've always been under the impression that friction modifiers are different than antiwear additives though. Am I wrong?

I thought antiwear additives were added in order to make the oil "more slippery" while friction modifiers were added to make oils "less slippery" such as in the case of motorcycle or diesel oils, or in the case of a limited slip differential or certain types of trannies which don't work as well with a more slippery oil.

Comments?
 
Friction modifiers are added to reduce friction or as Patman put it, to make the 'oil more slippery'. That's why it's best to avoid the use of oils with friction modifiers in motorcycles or other wet clutch applications.
 
There's plenty of functional overlap between these three types of oil additives, but they're not exactly the same thing:

1. Friction Modifier (FM) - reduces friction for better fuel economy and light anti-wear.

2. Anti-Wear (AW) - reduces friction and wear.

3. Extreme Pressure (EP) - reduces scoring and seizure under the heaviest loads.

Although it's possible, I've never heard of a FM being used to INCREASE friction in automotive applications. It would be more accurate to say "friction reducer," but it doesn't sound as cool as "friction modifier."

Vehicles with manual transmissions should avoid gear oil with FMs, since the synchros require a minimum amount of friction for smooth gear shifts. Since automatic tranmissions operate by pressure, the ATF works fine with FMs.
 
I think Patman was right in referring to Friction Modifier fluid that you add to limited slip diffs, it makes fluids less slippery for proper operation of the diff. Friction modifier additives in motor oil are likely different from Friction modifier LSD fluids, not to confuse the two terms.
 
Problem with friction modifiers is they have a very short service life, they are destroyed by the first 500 kms of service. Therefore they're there only to get a vehicle manufacturer passed the CAFE tests and to get whatever API or ILSAC energy conserving label applies.

I think that if a vehicle manufacturer uses a friction modififed engine oil to pass CAFE tests, then they have to state that these oils must be used in their owners manuals. But most friction modified oils are ineffective over most of the service life of the oil.

I recall that Texaco Europe had an engine oil which had a friction modifier which lasted right through the oil change. Some in service testing proved fuel saving around the 6% level throughour the oil change interval, but I can't remember what the reference oil it was tested against.

This was Texaco Havoline Energy SAE 5W-30, and this oil was used in the Stewart and subsequent Jaguar formula 1 engines while Texaco had the sponsorship. I still use it now, its one of few SAE 5W-30 oils you can get down here in New Zealand.

But as friction modifiers reduce internal engine friction there is the double effect - either reduced fuel consumption or increased power with the same fuel consumption.

[ June 02, 2004, 07:19 PM: Message edited by: SteveS ]
 
To the best of my knowledge, friction modifiers in limited-slip differentials are only used to reduce friction. To increase friction, FMs simply aren't added to the oil.

[ June 03, 2004, 04:45 PM: Message edited by: Bruce T ]
 
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