What Is Dexos Oil?

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mx5miata

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The dexos specification is exclusive to General Motors, and any oil carrying the dexos logo is suitable for meeting GM warranty requirements. To meet the dexos requirements, an oil must typically be synthetic or a synthetic blend. GM stated that dexos was introduced to simplify oil selection and ensure increased fuel mileage. The American Petroleum Institute and the International Lubricant Standardization and Approval Committee have similar oil ratings.

Why am I coming across posts that Dexos is a product that makes up the oil.

How does "Dexos" protect timing chains. timing chains been around longer than Dexos rating.

when I look up Dexos it comes back as an oil approved by general motors.
 
I dont own any GM vehicles so i could care less. My oils i use dont "pay to play" the DEXOS games created by GM

i have used a Dexos 1 gen 2 oil in the past without any ill effects
smile.gif
 
It is a performance specification that is higher than SN rated oils; the specification was developed by GM.

Quote:

i could care less.


Could or couldn't? j/k
 
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Dexos is just a spec that GM came up with.
They get a kickback on every oil sold wearing the Dexos label.
Sounds like GM made engines need specialized oil in order to last and to keep warranty claims down.
 
From the few pictures I’ve seen, the timing chains of today look like heavy duty bicycle chains, not the wider chains of yesteryear before belts became popular.
 
Never followed the Dexos thing myself. My wife's Chevy Spark had a Suzuki engine, so any old 5w20 went in that sump.
 
https://passenger.lubrizoladditives360.com/specifications/oem-dexos/#dexos1™:%20New%20Tests
 
Funny how lots of members here decry GM's Dexos specs, but are fine with the likes of Porsche A40, MB229.XX, Ford WSS-XXXXXX-X specs, etc....
 
My Dad was an engineer with General Motors, working mostly in the Allison aircraft engine side. He told me that GM put tremendous effort into research and formulation of lubricants, working closely with chemical engineers from multiple lubricant manufacturers and suppliers.

I believe there is more to this than just marketing. I think with thinner oils, GM likely found some areas of concern with these new oils and some of the engine technology, such as DI, and other design features intended to increase efficiency, which could include timing chains designed to reduce mass and friction. They decided they needed specific performance criteria to work with their engines, so they developed the Dexos certification. I doubt it is a hugely expensive deal, since many generic brands appear to be formulated to meet it, along with the big brands.

Does it cost money to be certified for Mercedes? Chrysler? Ford? Probably. I'm not sure why GM is getting flogged for this. It is their right to do as they please, and it appears most oil manufacturers have bought in. Good on them. If it reduces warranty claims, how exactly is that a bad thing, for anybody?
 
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If you do a little online research, you will find that alot of 4 cyl GM motors have oil consumption issues. Claiming to be from prematurely worn piston rings. Along with timing chain wear issues, which is probably why GM is strong arming / using scare tactics to anyone who will listen about using their "Dexos" rated oil. It seems to me the oil the recommend isn't protecting your car as well as it should for what it costs, if their motors are using alot of oil after 120k miles. I'm not saying oils that pay to carry the symbol on their oil containers are bad oils,just that there seems to be some other issue possibly poor engineering of the motor that's being ignored. And blamed on the end consumer using inferior oil products in GM cars.,,
 
Originally Posted By: BigCahuna
If you do a little online research, you will find that alot of 4 cyl GM motors have oil consumption issues. Claiming to be from prematurely worn piston rings. Along with timing chain wear issues, which is probably why GM is strong arming / using scare tactics to anyone who will listen about using their "Dexos" rated oil. It seems to me the oil the recommend isn't protecting your car as well as it should for what it costs, if their motors are using alot of oil after 120k miles. I'm not saying oils that pay to carry the symbol on their oil containers are bad oils,just that there seems to be some other issue possibly poor engineering of the motor that's being ignored. And blamed on the end consumer using inferior oil products in GM cars.,,


Wow, lots of assertions here. Care to provide evidence? Which engines? Source? Scare tactics? Really? How so?

There are a number of 4 cylinder engines in our family, many with well over 100k miles, and I know of not a single one having these issues. They include 2.4 Ecotecs (Malibus, Equinoxes), and 1.4 Turbos (Cruz). They all have followed their oil life monitors and used the recommended oils. No issues. That's anecdotal, but I'd think out of the 5 vehicles I'm thinking of, you'd see something if there was a design flaw. None report using any oil, either. An Equinox and Cruz, owned by my brothers, get absolutely flogged. Those guys are good on maintenance, but they run their engines very hard, putting lots of miles on them in the process. Both love their vehicles and engines. The others in the family are pretty average drivers that don't drive for fun, but to get from A to B.
 
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IF I were to rethink the oils going into my autos (with the intent of trying something new), I would base my new selection a lot on what I see here on bitog UOAs. Practically all oils nowadays are ok, but if I were looking for that needle in the haystack unicorn oil, the UOAs here would play a part. Dex specs not so much.
 
GM didn't create Dexos with the idea of helping out their customers.
It was done to lower warranty claims and to profit off of the public thinking that they must use the Dexos spec or any claim will be denied. A pure money grab.
 
The new Dexos1 Gen 2 stuff might be better at protecting some of GM's motors, but the Gen 1 stuff was not all that spectacular. Especially in regards to AFM failure rates and oil consumption from coked piston rings in some of the deactivated cylinders. So it is a real stretch to lay out the case that GM's engineers were all that diligent in coming up with a specification that was ahead of everything else for their motors. It is the potpourri of engine oil specifications that are as diverse as the number of different OEM's that is getting stupid. And many times, they are designed as some sort of bandaid for cost cutting R&D.

But to be fair, I think the main reason GM came up with this dexos thing was to prevent owners from being motivated to throw in the lowest quality oil in their motors. It was primarily an attention getter GM did on their product buyers and they word it in such a way in their owner's manuals to scare folks into thinking that they will void the warranty if they do not use the exact same designation as GM specifies. dexos is not heads and shoulders above even API SN. It does edge out SN in some areas, but SN edges out dexos in some others. Like ethanol emulsification. GM touts flex fuel capability on many of their motors, virtually all motors are going to have to ingest at least E10 at some point, but dexos is not up to the same level as API SN and ILSAC GF-5 at dealing with ethanol emulsification. If GM is so astute regarding motor oil formulation as it pertains to their motors, then how did this one slip thru the cracks? And in what other ways did they make similar goofs?

It is almost as bad as the Ford / CK-4 HDEO nonsense. There is an OEM that comes out and lambasts the new CK-4 as an inferior product for their diesel motors, but their list of accepted CK-4 oils in 10w30, 5w40, and 15w40 flavors just continues to grow. Would have been much better if Ford had kept it's stupid mouth shut and not cause their clientele to suffer from a massively inflated paranoia glandular condition and wonder if their warranty would be voided because the oil they were using was not on the Ford alphabet soup of specifications. It is this kind of nonsense that I remember when it comes time to shop for another vehicle. It is a checkmark in the "con" column. And no, I do not own a Ford, but I know stupid from an OEM when I see it. They have enough problems with their EcoBoost stuff that should consume most of their time instead of scaring the pants off their diesel pickup owners also.
 
First of all, I believe the maximum oil weight to meet Dexos is 30, so the high viscosity folks need not apply. I was thinking that the Dexos spec was part of the re-design for the infamous AFM problems but someone chimed in that the Corvettes get xW40 oil and they have AFM. Can’t answer to that conundrum.

I looked at the VOA’s and noticed most D1G2 oils have some Moly in them. I’m thinking I haven’t seen any TBN data. Zinc and Phosphorus are pretty normal. They don’t get carried away on Calcium as the highest I’ve seen so far is 1715 ppm. They often contain Titanium but not always. If the base oil is different, I haven’t seen anything on it. If anyone can fill in the gaps without breaking into a conspiracy theory I’d be interested in reading it.

smile.gif
 
And in a couple of years we'll be posting, "whatever happened with Dexos?" Like f a r t i n g in the wind it all blows away.
 
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