Engine Noise From Synthetic Oil - Does It Do Damag

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So lots of talk about some synthetic oils causing more engine noise than others. Mobile 1 seems to be one of the "noisiest", but with that noise is there any concern about actual damage or wear to engines?

It would seem a quite and smooth running engine is suffering less damage than a real noisey one caused by, say Mobil 1 synthetic. Is this true, or is the "noise" nothing to be concerned with?
 
Originally Posted By: Verminator
but with that noise is there any concern about actual damage or wear to engines?

There is no evidence to support this assumption.
 
That would mean excessive metal to metal contact, the engine wouldn't survive very long if that were the case.
IMHO too much is made of this "my engine is quieter with x oil than with y oil".
I may have a tin ear but although there may be some extremely slight acoustic difference i never heard anything that would worry me.
 
Wonder what the science is behind what makes certain oils "noisier" per se? I'm just very curious by nature,and I guess I just find this particular subject facinating.
 
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Certain oils may be smoother and quieter in a given engine than others.
There is nothing to support the position that noisier equates with more wear.
M1 is often reported to be a noisy oil by many users, yet M1 in all its grades and flavors typically yields very good numbers in UOAs on extended drains.
It also appears to keep engines nice and clean internally.
While I'd probably avoid an oil that made my engines seem rougher and louder, I'd not worry that the apparent increase in noise meant a concomitant increase in wear.
 
Originally Posted By: fdcg27
Certain oils may be smoother and quieter in a given engine than others.
There is nothing to support the position that noisier equates with more wear.
M1 is often reported to be a noisy oil by many users, yet M1 in all its grades and flavors typically yields very good numbers in UOAs on extended drains.
It also appears to keep engines nice and clean internally.
While I'd probably avoid an oil that made my engines seem rougher and louder, I'd not worry that the apparent increase in noise meant a concomitant increase in wear.



Exactly. I basically wrote this in your other thread OP about m1 being more noisy than some other oils.

A noisy engine is what pushed me away from M1 years ago and led me to amsoil. Every engine I ever put M1 into was more noisy than other oils. I've found this was consistent with the 20w-50 v-twin oil in my Harley too.
But it's just noise and has absolutely nothing to do with the oils ability to perform as required. Maybe its because M1 engines are so clean inside there's no deposits to absorb the sound waves hence the engine appears to be more noisy.
I'm no fan of Mobil in fact I hate the company as a whole however I will admit they've got a consistent product line that is pretty much perfect in regards to their ability to keep engines clean as well as holding just about every major oem engine certification that can be had.
And their 0w-40 is something very special. Its one of the best oil son the planet and if I lived in America I would use it exclusively in everything I own regardless of what the oem called for.
 
M1 15W50 is definitely one of my fave oils. Smooth as silk and silent in every car I've used it in. Maybe its the super strong add pack it has? That oil seems to have legendary status on the net.
 
Originally Posted By: Quattro Pete
Verminator said:
but with that noise is there any concern about actual damage or wear to engines?

That noise you hear is Mobil 1 destroying your engine. Mobil 1 almost always leads to Imminent failure.
 
Originally Posted By: Realtech214
Originally Posted By: Quattro Pete
Verminator said:
but with that noise is there any concern about actual damage or wear to engines?

That noise you hear is Mobil 1 destroying your engine. Mobil 1 almost always leads to Imminent failure.


+1. That's why Corvette, Porsche, MB, and many other of the leadeing autos in the world recommend it as FF. And even more important, it has ruined most of my engines I have used it in for the last 36 years. But I have hope it will improve.
18.gif
 
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Originally Posted By: Clevy
I'm no fan of Mobil in fact I hate the company as a whole however I will admit they've got a consistent product line that is pretty much perfect in regards to their ability to keep engines clean as well as holding just about every major oem engine certification that can be had.
Ditto.

I did notice a "change" in the sound of my DD when I switched from MC 5W-20 to M1 5W-30 (to use up a left-over jug), but I have no qualms about it. M1 is an excellent oil.
 
Elastohydrodynamic-lubrication (EHL) film thickness is given by (reference):

Backup_200403_lubselect-form2.gif


Here H_c is the EHL film thickness, alpha is the pressure - viscosity coefficient, and eta_0 is the high-shear (HTHS) viscosity.

The goal is to have the pressure - viscosity coefficient as high as possible, as well as the HTHS viscosity, to achieve a higher EHL film thickness.

Unfortunately, Group IV (PAO) has the smallest pressure - viscosity coefficient, followed by Group III, which is followed by Group II. Group I has the largest pressure - viscosity coefficient. Here is why (from page 180 of the reference):

presssure-viscosity.jpg


presssure-viscosity_graph.jpg


Therefore, synthetic oils will give smaller oil film thickness than Group II oils and Group II oils will give smaller oil film thickness than Group I oils in the EHL regime. EHL regime and boundary-lubrication regime both apply to the valvetrain.

One advantage of synthetic oils is that, due to their use of lower concentration of viscosity-index improvers, their HTHS viscosity will shear less than for conventional oils over the OCI. Higher HTHS viscosity is good for oil-film thickness. Therefore, synthetic oils will maintain their oil-film thickness better than conventional oils over the OCI.

After all this said, am I worried about using synthetic oil? No, I am not. I believe the most important protection against wear in the valvetrain is ZDDP, moly, and other antiwear additives. So, if you have a decent concentration of quality (mostly secondary kind) ZDDP, the trinuclear kind of moly, and some additional quality AW/EP/FM additives, you should have good wear protection in the valvetrain regardless of the viscosity or the pressure - viscosity coefficient. This is not a proven statement though but more my current understanding. Engine tests are always the most authoritative in reaching a conclusion.
 
I've used M1 15W-50 in three different cars.
It is very quiet and very smooth, but anything that thick would be.
For the record, fuel economy was also okay with this oil.
The high HTHS didn't seem to hurt fuel economy much if at all.
 
Originally Posted By: Gokhan
Elastohydrodynamic-lubrication (EHL) film thickness is given by (reference):

Backup_200403_lubselect-form2.gif


Here H_c is the EHL film thickness, alpha is the pressure - viscosity coefficient, and eta_0 is the high-shear (HTHS) viscosity.

The goal is to have the pressure - viscosity coefficient as high as possible, as well as the HTHS viscosity, to achieve a higher EHL film thickness.

Unfortunately, Group IV (PAO) has the smallest pressure - viscosity coefficient, followed by Group III, which is followed by Group II. Group I has the largest pressure - viscosity coefficient. Here is why (from page 180 of the reference):

presssure-viscosity.jpg


presssure-viscosity_graph.jpg


Therefore, synthetic oils will give smaller oil film thickness than Group II oils and Group II oils will give smaller oil film thickness than Group I oils in the EHL regime. EHL regime and boundary-lubrication regime both apply to the valvetrain.

One advantage of synthetic oils is that, due to their use of lower concentration of viscosity-index improvers, their HTHS viscosity will shear less than for conventional oils over the OCI. Higher HTHS viscosity is good for oil-film thickness. Therefore, synthetic oils will maintain their oil-film thickness better than conventional oils over the OCI.

After all this said, am I worried about using synthetic oil? No, I am not. I believe the most important protection against wear in the valvetrain is ZDDP, moly, and other antiwear additives. So, if you have a decent concentration of quality (mostly secondary kind) ZDDP, the trinuclear kind of moly, and some additional quality AW/EP/FM additives, you should have good wear protection in the valvetrain regardless of the viscosity or the pressure - viscosity coefficient. This is not a proven statement though but more my current understanding. Engine tests are always the most authoritative in reaching a conclusion.


Nice post, very interesting about the P-V co with the common bases

One thing about this discussion worth noting is that "synthetic" should not be directly correlated to "engine noise". Not every friction surface 'style' (gear, rocker arm, tappet bucket and the various individual designs thereof) across engine manufacturers respond the identically to various oil formulas. Also, some synthetics like GTL and POE seem to have superior 'damping' than others, similar to lower group bases. If someone has Pressure-Viscosity data for GTL/POE it's be awesome to see
wink.gif
 
Originally Posted By: tig1
Why do you guys hate XM? I hear you say it but no explaination.



Years ago I was an M1 fanboy. Then I got caught up in the whole basestock debacle,then the castrol hearings and I just swung over to the Amsoil bench.
And if you like a Amsoil you naturally have to hate Mobil.
Then I tried it out for old times sake and my engines got very noisy and I didn't like that they cheapened the basestocks after the castrol thing but the cost to the consumer didn't change so I just decided that's it,no more Mobil.
I'll buy the stuff when its cost effective and on sale but I won't go out of my way to search got it.

Originally Posted By: Gokhan
Elastohydrodynamic-lubrication (EHL) film thickness is given by (reference):

Backup_200403_lubselect-form2.gif


Here H_c is the EHL film thickness, alpha is the pressure - viscosity coefficient, and eta_0 is the high-shear (HTHS) viscosity.

The goal is to have the pressure - viscosity coefficient as high as possible, as well as the HTHS viscosity, to achieve a higher EHL film thickness.

Unfortunately, Group IV (PAO) has the smallest pressure - viscosity coefficient, followed by Group III, which is followed by Group II. Group I has the largest pressure - viscosity coefficient. Here is why (from page 180 of the reference):

presssure-viscosity.jpg


presssure-viscosity_graph.jpg


Therefore, synthetic oils will give smaller oil film thickness than Group II oils and Group II oils will give smaller oil film thickness than Group I oils in the EHL regime. EHL regime and boundary-lubrication regime both apply to the valvetrain.

One advantage of synthetic oils is that, due to their use of lower concentration of viscosity-index improvers, their HTHS viscosity will shear less than for conventional oils over the OCI. Higher HTHS viscosity is good for oil-film thickness. Therefore, synthetic oils will maintain their oil-film thickness better than conventional oils over the OCI.

After all this said, am I worried about using synthetic oil? No, I am not. I believe the most important protection against wear in the valvetrain is ZDDP, moly, and other antiwear additives. So, if you have a decent concentration of quality (mostly secondary kind) ZDDP, the trinuclear kind of moly, and some additional quality AW/EP/FM additives, you should have good wear protection in the valvetrain regardless of the viscosity or the pressure - viscosity coefficient. This is not a proven statement though but more my current understanding. Engine tests are always the most authoritative in reaching a conclusion.



So this explains why conventional oils tend to make an engine very quiet,because the oil film is thicker but not necessarily stronger.
Am I to infer that yes a conventional oil has a thicker oil film at any given temp however the film strength is lesser than their synthetic counterparts?
Thanks in advance for any answers if you know them.
 
Clevy,
Since I've used M1 oils through out all the formulation changes, I have never experienced any unusual engine noise or quality reduction. In fact I have noticed the quality of M1 oils for the last 36 years have improved, as all other oils have.
 
Originally Posted By: tig1
Clevy,
Since I've used M1 oils through out all the formulation changes, I have never experienced any unusual engine noise or quality reduction. In fact I have noticed the quality of M1 oils for the last 36 years have improved, as all other oils have.


What have you got to compare current engine acoustics to though tig. If you've never used anything but M1 you have nothing to compare it against whereas I use a different oil at every oil change so I can compare acoustics directly and I remember what the last oil change sounded like etc etc.
 
Originally Posted By: Merkava_4
Why do we oil a door hinge or a bicycle chain? Because it's noisy.

The sound of good lubrication is no sound.



Maybe when I comes to a bike chain or door hinge however neither compare to an engine.
First of oil film thickness isn't as relevant as oil film strength. So a thinner film can be stronger than a thicker oil film even though the thicker film will mask more noise.
I don't know where you get this stuff from but one has nothing to do with another.
You know some varnish will dampen sound eh,so maybe you're engines aren't noisy because of the thick skin of varnish on the top end.
 
Originally Posted By: Merkava_4
Why do we oil a door hinge or a bicycle chain? Because it's noisy.

The sound of good lubrication is no sound.


And this is exactly what concerns me! It's hard for me to accept that Mobil 1 5W30 causes a great deal more engine noise, yet that noise is not caused from moving parts that appear not to be lubricated properly...even though I'm told the science behind it says the parts ARE being properly lubricated...
 
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