Do synthetics reduce friction?

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Just cut and pasted this from a NORIA newsletter email today. Sure it's old news to most the folk here but i found it interesting:


Book Bits: Do Synthetics Reduce Friction?

From "How to Select a Motor Oil and Filter for Your Car or Truck"

Some synthetics, such as diesters and polyol esters have natural lubricity. Other synthetics, such as PAOs, offer no enhanced antiwear or friction-reducing properties by themselves. However, formulated motor oil generally consists of a blend of base oils plus additives that collectively impart friction and wear-reducing performance properties. PAO is the most common synthetic fluid used in motor oil formulations. It is frequently blended with a small concentration of an ester, such as a diester, to reduce seal shrinkage, improve additive solubility and provide better lubricity. However, it is worth noting that a mineral oil can be blended with esters and antiwear additives to achieve similar results.
 
What he is saying is true, but I always though PAO's are better at reducing friction. I know Esters do. Good question.
 
I am going to guess that in the antiwear properties PAO is like dino. But PAO does IIRC have better cold and hot properties than even Group III dino. Sill won't beat ester though.
 
How many of us actually run the oil past the 300 degree mark?

I see no particular reason viscosity to viscosity, there is any advantage of Synthetic over dino given similar additive packs.

There is no evidence that I know of that synthetics inerently have lower friction.

As for extended oil life, I there may be evidence that some synthetics display longer life times in use than some dinos. Although some dinos show similar results, i.e, Havoline and Motorcraft.

As far as UOA's are concerned, I suggest that trying to relate results between diferent engines, driving conditions is only useful as a potential tool for trying to "home in" on a oil. In the end, one must try for themselves an oil and see how it performs for you.

In general, I blieve any of the SM oils will do well. Providing temperature and driving conditions are taken into account.
 
Is it fair to say then dino oil is just as good as syn oil for summer conditions at over half the cost of syn oil and syn oil has its place for cold winter flow properties? I do ask this based on my policy of not extending OCI when I use syn oil.

Cyprs
 
quote:

Originally posted by buster:
but I always though PAO's are better at reducing friction. I know Esters do. Good question.

There are different types of PAOs. Maybe PAOs like Mobil's SuperSyn are better at reducing friction than the "average" PAO?
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Anyway, I think the advantage average PAOs have is their CCS, MRV performance while still having a decent VI for the rest of the temperature regime to include oxiation resistance, volatility, shear stability characteristics. Dinos may adequate for the normal users, but most BITOG members are most likely orthogonal users.
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quote:

Originally posted by Cyprs:
Is it fair to say then dino oil is just as good as syn oil for summer conditions at over half the cost of syn oil and syn oil has its place for cold winter flow properties? I do ask this based on my policy of not extending OCI when I use syn oil.

Cyprs


For most people in most vehicles I certainly think so; very definitely. I say that having 12 quarts of RedLine 10W30 on the shelf waiting for the end of my current OCI.
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I certainly think that synthetics are wiser in arctic conditions because of better low-temp flow/pumpability. I also think that many synths will keep an engine cleaner than most dinos, but that is not, IMHO, related to the base oil. It is related to the additives. Delo, Delvac, and Rotella will keep an engine awfully clean.
 
quote:

Originally posted by wileyE:

Some synthetics, such as diesters and polyol esters have natural lubricity. Other synthetics, such as PAOs, offer no enhanced antiwear or friction-reducing properties by themselves....

However, it is worth noting that a mineral oil can be blended with esters and antiwear additives to achieve similar results.


I have heard this many times. I really don't know, but I have come to believe it.
 
Hi,
I have been using (and pilot testing) synthetic oils since the early 1970's, in engines and gearboxes of all types and from the USA, Asia and Europe

IMHO (and without meaningful data to support it) I firmly believe the (reduction in friction)difference can be "felt" - sometimes immediately and at other times over a short period of time
In some cars a slight reduction in oil temperature has been measured but the operaing variables prevent calling this "conclusive evidence"

In gearboxes and diffs the reduction in friction can be measured in a reduced opearing temperature
I have much data supporting this proposition

Regards
Doug
 
Esters are a bit better than PAO's which are a slight bit better than Dino oils. It may actually be the higher amount of Ester in PAO that decreases the friction.
 
Yeah Bulwnkl, take Esso XD3, the add pack in 0-40 syn is nearly identical to the XD3 15-40 in specs and according to Esso tech when I asked about blending these oils, HDEO has high cleaning properties in Dino too.

Cyprs
 
quote:

Originally posted by 2003TRD:
So what oil is made from only esters? Isnt redline the only one? I thought that redline didnt always post the lowest wear numbers? I did find an interesting read on the TTORA forums,, what do u guys think http://p083.ezboard.com/ffjr1300own...essageRange?topicID=536.topic&start=1&stop=20

German Castrol, Delvac 1, Mobil 1 SUV Oil are very high in Estors (% unknown-to me).

Redline is almost all Ester. But keep in mind the base lubricant Ester, PAO, Group III, whatever does provide lubrication. But the additive package prevents wear when the "Full Film" lubrication breaks down. The best Estor would show terrible wear numbers in an automotive oil without proper additives.
 

I see no particular reason viscosity to viscosity, there is any advantage of Synthetic over dino given similar additive packs


PAO's and Esters based synthetic are more resistant to oxidation and sludge formation versus conventional base stocks.

I concur on the importance of additive suites, although Ester containing oils such as Redline and GC (pre-M05?) will out class your dino's.

The only problem with my argument would be HDEO's such as Mobi1 Delvac 1300 Super, Chevron Delo 400, etc. It is problematic comparing dino HDEO's to Premium Syns
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Using PAO and/or Ester based synthetics does result in significantly lower fluid temps - particularly under high loads in transmission/differential applications. However this is mainly due to the improved thermal conductivity of these fluids.

I have also seen consistent fuel savings with both synthetic engine oils - particularly the 0w-20/5w-20/0w-30 grades - and low vis, synthetic drivetrain fluids. I believe a lot of this is from a reduction in viscous losses during the warmup phase, which can be as much as 10-15 miles during cold weather. Note that coolant temps come to equilibrium much faster than oil temps in the engine/transmission/differential. The rapid rise in coolant temps is due to heating of the engine block from combustion gasses....

In addition, if you compare the VI's of synthetic lubricants to petroleum oils of the same SAE grade, the VI's of the synthetics can be much higher. So even though they may technically test out to the same SAE grade, the synthetic will easily meet the spec, while the petroleum oil barely will. For example, the CCS viscosity of a typical 10w-30 is about 5000-6200 Cp @ -13F and the VI's are in the 130-145 range. By comparison, the CCS viscosity of the PAO based, 10w-30/"ATM" formulation is only 3100 Cp @ -13F and it has a VI of 174. So pumpability of the 10w-30 synthetic is significantly better and it will provide improved fuel efficiency and lower fluid temps.

Finally, I also think that the PAO/Ester synthetics provide improvements in upper cylinder lubrication at the ring/cylinder interface, as well as in the very high pressure zones in the valve train. If you can avoid boundary lubrication conditions, friction in the valvetrain is significantly reduced.

I have not done enough controlled testing of Group III synthetics to know if they offer the same advantages of PAO's and Esters. But I intend to do this type of testing in the near future, using the Amsoil "XL" line of Group III oils.
 
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