Is DEXOS 1 the most "stringent" US gasoline oil specification?

[CarbonSteel]

Hopefully not beating a dead horse or repeating something, but of the main US gasoline specifications is Dexos the "best". For clarity I do not have any GM vehicles.

Ford has the WSS-XXXXXX-XX specification and Mopar has the MS-XXXX, I purchased both of these standards and they essentially state that if the oil meets API-SP and ILSAC GF-6A it meets the requirements.

Dexos seems to take that to a higher level or at least shows how it improves over API and I get that a chart like this does not prove anything. Just curious about the Dexos specification requirements over the others. I am also wondering if using Dexos approved oils means you are (at least in theory) getting a higher level of protection.

Thanks for the thoughts...

 

[Brian123]

Hopefully not beating a dead horse or repeating something, but of the main US gasoline specifications is Dexos the "best". For clarity I do not have any GM vehicles.

Ford has the WSS-XXXXXX-XX specification and Mopar has the MS-XXXX, I purchased both of these standards and they essentially state that if the oil meets API-SP and ILSAC GF-6A it meets the requirements.

Dexos seems to take that to a higher level or at least shows how it improves over API and I get that a chart like this does not prove anything. Just curious about the Dexos specification requirements over the others. I am also wondering if using Dexos approved oils means you are (at least in theory) getting a higher level of protection.

Thanks for the thoughts...

View attachment 186378

So, if you are not driving a GM, then what are you Driving?

 

[kschachn]

You're not necessarily getting a higher level of protection as compared to other independent requirements. Those aren't absolute values in the spider charts, they are areas of emphasis for that specific specification or approval.

Some specification may have been chugging along for years with no specific emphasis on catalyst protection for example, then due to market changes all of a sudden it becomes a priority. The chart would be extended for that specific consideration. It may be that for some other specification or approval it has always been a priority (and may very well be better) but because the other spec was "deficient" then it looks like the one has this amazing ability. This happens all the time with specifications and approvals and is particularly relevant to dexos. The chart you posted is really only relevant for comparing d1G1 vs. d1G3 and only as a relative indicator. Some spider chart for Mercedes-Benz 229.51 approval may look lower on all counts but overall might be a much better oil in every respect based on actual values.

 

[JohnnyG]

It appears to me that 229.5 MB still has it beat. But I've been warned before that the comparison chart is not to be used for comparisons.
So who knows.

 

[twX]

I'd take the spider chart with a grain of salt. Most of the engine tests for Dexos 1 Gen 3 are different versions of tests that already exist for API SP, and I've never seen good evidence that they are actually more stringent. GM may have included these tests either because they are more stringent, or just because they are more representative since they use GM engines and not some ancient Chrysler V6. I would bet that most of them are more stringent than the tests for API SP.

One area where Dexos 1 is definitely better than API SP is the sludge test, since it uses the same method but with a much more stringent requirement to get a passing grade. It also requires lower NOACK using the same test method.

 

[chris719]

Dexos R probably

 

[nascarnation]

It always comes down to what failure mode are you trying to protect against. If your vehicle has a known deficiency, or specific outlier duty cycle, smart folks on here may be able to point you toward a possible best solution. For 97% of the vehicle population, the Dexos spec is likely sufficient. The fact that the average age of the US vehicle fleet is at an all time high (12.2 yrs) says the industry is probably doing OK with this.

 

[bbhero]

You're not necessarily getting a higher level of protection as compared to other independent requirements. Those aren't absolute values in the spider charts, they are areas of emphasis for that specific specification or approval.

Some specification may have been chugging along for years with no specific emphasis on catalyst protection for example, then due to market changes all of a sudden it becomes a priority. The chart would be extended for that specific consideration. It may be that for some other specification or approval it has always been a priority (and may very well be better) but because the other spec was "deficient" then it looks like the one has this amazing ability. This happens all the time with specifications and approvals and is particularly relevant to dexos. The chart you posted is really only relevant for comparing d1G1 vs. d1G3 and only as a relative indicator. Some spider chart for Mercedes-Benz 229.51 approval may look lower on all counts but overall might be a much better oil in every respect based on actual values.

Not trying to give you a hard time here my friend… Not at all.. Just sharing what I have read and observed in regards to this circumstance.

Well when you compare say API SM against Dexos it is clearly evident that Dexos is way, way tougher specification to meet. .

And no one on here would think that is a question.

And when you compare say MB 229.5 and or Porsche A40 to say API SM or API SN It’s not even close to being a contest.. . Which makes sense given the actual parameters needed to meet MB 229.5 .. Volatility less than 10 percent vs API SM at 15 percent.. Not to mention the actual measurements of deposits allowed by each of those specs or actual wear allowance by each of those specs against one another… Which the Afton handbook actually has those results/ numbers available..,

Which I have looked at and those results make sense in relationship to those spider charts. Even when comparing API SM vs Dexos Gen 1…

The MB and Porsche approvals without question beyond API SM or even API SN. By a good margin. The Afton handbook clearly had the testing parameters and expected results and it again dove tailed with a spider chart comparison of those different specs/ approvals against each other.

Does that mean a MB 229.5 oil would be “ better” at west protection vs API SM, API SN ?

Well look at the total wear number allowed by each of those requirements.. . It’s not hard to see that MB and Porsche are well better at that vs API SM or API SN.

Or that those specs still are a fair amount tougher than API SP.. . They are. The test parameters are still tougher by a good margin in terms of volatility, wear and deposits allowed.

API has slowly been closing the gap to being more like Dexos. Which obviously means those standards are getting a bit by bit closer to those other Euro specs. Still a decent way off to those even at this time.

 

[Nesterenko]

but of the main US gasoline specifications is Dexos the "best"

?

 

[SubieRubyRoo]

I'm just trying to figure out how with all its supposed excellence (and thousands of threads), 99% of people here don't even know that Dexos, DEXOS, and any other capitalization besides "dexos" is wrong? Maybe GM should up the license fee so they can spend more money marketing the brand, especially to those whose engines don't even recommend using it!

SMH /rant
Good night!

 

[RooflessVW]

Dexos R probably

More likely dexos2 or dexosD, both being for diesels with after treatment.

 

[kschachn]

Not trying to give you a hard time here my friend… Not at all.. Just sharing what I have read and observed in regards to this circumstance.

Well when you compare say API SM against Dexos it is clearly evident that Dexos is way, way tougher specification to meet. .

And no one on here would think that is a question.

And when you compare say MB 229.5 and or Porsche A40 to say API SM or API SN It’s not even close to being a contest.. . Which makes sense given the actual parameters needed to meet MB 229.5 .. Volatility less than 10 percent vs API SM at 15 percent.. Not to mention the actual measurements of deposits allowed by each of those specs or actual wear allowance by each of those specs against one another… Which the Afton handbook actually has those results/ numbers available..,

Which I have looked at and those results make sense in relationship to those spider charts. Even when comparing API SM vs Dexos Gen 1…

The MB and Porsche approvals without question beyond API SM or even API SN. By a good margin. The Afton handbook clearly had the testing parameters and expected results and it again dove tailed with a spider chart comparison of those different specs/ approvals against each other.

Does that mean a MB 229.5 oil would be “ better” at west protection vs API SM, API SN ?

Well look at the total wear number allowed by each of those requirements.. . It’s not hard to see that MB and Porsche are well better at that vs API SM or API SN.

Or that those specs still are a fair amount tougher than API SP.. . They are. The test parameters are still tougher by a good margin in terms of volatility, wear and deposits allowed.

API has slowly been closing the gap to being more like Dexos. Which obviously means those standards are getting a bit by bit closer to those other Euro specs. Still a decent way off to those even at this time.

That may be true but the spider chart still isn't the tool to show that. It may show it but you'd really have to look at the specific requirements and compare absolute numbers to make a valid comparison.

 

[Nesterenko]

I'm just trying to figure out how with all its supposed excellence (and thousands of threads), 99% of people here don't even know that Dexos, DEXOS, and any other capitalization besides "dexos" is wrong? Maybe GM should up the license fee so they can spend more money marketing the brand, especially to those whose engines don't even recommend using it!

SMH /rant
Good night!

dexos1 GEN 3

 

[I<3oil]

I'm just trying to figure out how with all its supposed excellence (and thousands of threads), 99% of people here don't even know that Dexos, DEXOS, and any other capitalization besides "dexos" is wrong? Maybe GM should up the license fee so they can spend more money marketing the brand, especially to those whose engines don't even recommend using it!

SMH /rant
Good night!

also have put the little TM at the end of it too

 

[RooflessVW]

also have put the little TM at the end of it too

It's actually the Registered symbol and it goes after dexos but before the quantifier.

dexos®1
dexos®2
dexos®D
dexos®R

Maybe the forum needs autocorrect?

 

[I<3oil]

It's actually the Registered symbol and it goes after dexos but before the quantifier.

dexos®1
dexos®2
dexos®D
dexos®R

Maybe the forum needs autocorrect?

the symbol is the little R but if can't do symbol and write it out, it's the TM

 

[bbhero]

That may be true but the spider chart still isn't the tool to show that. It may show it but you'd really have to look at the specific requirements and compare absolute numbers to make a valid comparison.

Well the chart verifies that Dexos is tougher by having a lower 12.5 percent maximum burn off volatility vs API SM which was 15 percent via the chart… By looking at oxidation control… Piston cleanliness and sludge deposits.. All of which validate and verifies an oil with lower 12.5 percent vs 15 percent volatility would clearly have those benefits.

Furthermore MB 229.5 and Porsche A40 and C30 do the same thing with volatility limited to a maximum of 10 percent vs API SP and even Dexos… Same thing here… Oxidation, piston deposits and less sludge all point to a oil with tougher specs and a 10 percent limit of volatility vs one that allows a higher volatility of 15 percent.

It’s not hard to see those differences.

This is analogous to arguing about a person’s blood lab results where their potassium level is 6.3 and wondering why their heart rate is unstable… Well… the lab result is right there in front of me… Cause and effect…

Better Noack being 10 or less vs 15 percent gives the results in better oxidation, less deposits and cleaner pistons.