Is Synthetic Oil Really Proven to Clean?

[Viet]

I have read countless threads about engine flushes and using oils such as Yellow Bottle and Mobil 1 Clean 5000 to clean out sludge and varnish. I always see a few people talk about using synthetic oil to maintain cleanliness. I haven't been able to locate anything that proves that synthetic oil cleans.

To those that say that synthetic cleans....

Are you referring to group III oils or group IV?
and can someone point me in the direction of some proof that synthetic oil cleans?

 

[charbaby]

Well, I can't really do any justice here but, I'll share a little of what I have learned here at Bob's.

Synthetic Oils by themselves may or may not do a better job of cleaning. But, syn oils do/did have more cleaning additives such as calcium and others in their additive package which did a better job of cleaning. So, synthetic oil typicaly has more cleaning agents than conventional oils. But too, I would have to say, not in every instance and may vary between brands/grades.

 

[Y_K]

Syn oil is a detergent by itself.

 

[Viet]

Originally Posted By: Y_K
Syn oil is a detergent by itself.

Grp III or IV?

 

[fdcg27]

I think cleaning depends more upon the detergent additives than upon the basestock used.
Now, having said that, it may be that Grp V oils do have particualarly good cleaning performance.
I base this upon ARX being an ester based product, as well as some really high iron numbers in used oil analysis of both RL and RLI oils, both of which have significant ester content.
The speculation here was that it was more likely that the oils were cleaning deposits left behind by previous oils than that they were really causing excess wear.
Esters are highly polar, so they seek to attach to metal surfaces, displacing any deposits in the process, or at least that is how I understand it.

 

[Scienceman]

I should be CLEAN! LOL!

 

[widman]

The only way synthetic cleans better is is it has a high ester content or more detergent. You can easily find as much detergent in a mineral oil.

Normal synthetics are less solvent than many oils, but it is compensated with esters.

Just like anything else, you have to be specific.

 

[Y_K]

Originally Posted By: Viet
Grp III or IV?

Grp V
Also, alcohol in E10

 

[Pablo]

Originally Posted By: widman


Just like anything else, you have to be specific.


Exactly.

Amsoil HDD and ACD WILL clean your engine very nicely. Is it the base oils or the additives?

IMHO - synthetic base oils REALLY do help keep your rings cleaner and overall engine internals cleaner in very general terms, but there are many variables in the equation.

 

[JHZR2]

We certainly know that synthetic fuels (F-t derived) significantly clean residues from conventional fuels.

The basestocks used in oils are different, but they have solubility.

It is a matter of both, adds and basestocks.

 

[Capa]

It seems to me that the OP is asking whether synthetic oils clean rather than do they clean better than conventional oil. I don't understand how anyone can question whether synthetics clean. In fact, according to Pennzoil, their synthetics clean better than their conventional oil and apparently better than other synthetics. All oils clean to varying degrees regardless of whether they are synthetic or not.

 

[tig1]

Since I have used Mobil 1 oils for 33 years now, I haven't had any sludge to clean up in that time, but I do believe Syn oil will help clean engines that have some sludge.

 

[Warstud]

There are many reports of oil leaks when using syn. oil because they cleaned out the dirt that plugged up a previous leak from using oil that had fewer cleaning agents.... example (conventional oil).

 

[Viet]

Would Castrol Edge be considered the top cleansing oil that Castrol produces?

 

[OVERKILL]

Originally Posted By: Warstud
There are many reports of oil leaks when using syn. oil because they cleaned out the dirt that plugged up a previous leak from using oil that had fewer cleaning agents.... example (conventional oil).


Yup, I've experienced that one first-hand.

 

[sxg6]

Originally Posted By: Viet
I always see a few people talk about using synthetic oil to maintain cleanliness. I haven't been able to locate anything that proves that synthetic oil cleans.

To those that say that synthetic cleans....

Are you referring to group III oils or group IV?
and can someone point me in the direction of some proof that synthetic oil cleans?


I think your original post says it all. There is no proof that synthetic oil has any cleaning abilities. Developing a leak after switching to synthetic is not a convincing argument.People can say oh well group V basestocks have cleaning properties. Ok, well, there are many different types of group V basestocks. Aside from that, how do we know which oils have some, if any group V base, and how much they have? And if they do in fact contain a small amount, is it enough to have any sort of cleaning abilities?

My .02 is that synthetic oils do a great job of maintaining a clean engine, but I'm not convinced they have the ability to clean a dirty engine.

 

[gfh77665]

Originally Posted By: sxg6
Developing a leak after switching to synthetic is not a convincing argument.


OK, just asking, what would that indicate? Why does it happen?

 

[sxg6]

There are many reports of people switching to synthetic and developing a leak, and switching back to conventional oil and the leak disappears. So if the synthetic oil cleaned up gunk which had been plugging a potential leak, wouldn't they continue to have leak issues even after switching back to conventional?

 

[OVERKILL]

Originally Posted By: sxg6
Originally Posted By: Viet
I always see a few people talk about using synthetic oil to maintain cleanliness. I haven't been able to locate anything that proves that synthetic oil cleans.

To those that say that synthetic cleans....

Are you referring to group III oils or group IV?
and can someone point me in the direction of some proof that synthetic oil cleans?


I think your original post says it all. There is no proof that synthetic oil has any cleaning abilities. Developing a leak after switching to synthetic is not a convincing argument.People can say oh well group V basestocks have cleaning properties. Ok, well, there are many different types of group V basestocks. Aside from that, how do we know which oils have some, if any group V base, and how much they have? And if they do in fact contain a small amount, is it enough to have any sort of cleaning abilities?

My .02 is that synthetic oils do a great job of maintaining a clean engine, but I'm not convinced they have the ability to clean a dirty engine.


I'm sure most of the major oil companies would disagree with you.

Image courtesy of buster:

 

[GMorg]

Synthetic oils (Grp III,IV, and V) will keep engines cleaner due to higher stability of the base oils. More heat stable means less coking and less varnish. Group III and IV base oil have the least ability to clean in and of themselves. However, esters and group I oils can do some cleaning. The problem with Group I oil is that it can produce more deposits than it removes.

So for the most part, the add package cleans (esters are an exception). Synthetics produce less deposits (all three groups). The recent trend has been to use more stable base oils with better add packages to produce oils that clean and have reduced deposit formation.

Group III and IV oils are nothing like detergents! The polar nature of esters has some characteristics similar to detergents.

Other than the physical nature of the chemicals involved, I'm not sure what I can offer as "proof". In the end, a given oil may or may not clean a particular deposit depending on the deposit. Detergents clean and yet I have jeans with 15 year old grass stains in the knees. Nothing cleans everything.