Dexos 1 - GM Oil Spec LogoIt appears that GM has decided that API and ILSAC classifications are not robust enough to offer the protection and longevity they are looking for in a motor oil for their vehicles. As a result, it looks like they've decided to roll out the new dexos 1 motor oil specification specific to the GM brand. Of course, this isn't exactly something new.

European OEMs have been establishing their own motor oil specifications for years, requiring oil manufacturers to not only address the requirements of ACEA licensing but also those of their own proprietary specifications. In addition, even in the US, it has long been common for vehicle OEMs to place additional requirements on the lubes that are to be used for certain vehicles.

However, this is a giant leap from the currently accepted norm, where OEM specs are typically established only for specific vehicles that truly require the additional protection guaranteed by adherence to a more robust OEM specification. In this case, GM appears to be looking to require this new "dexos 1" specification for all motor oils which are to be used in ANY of their vehicles. In this way, claims GM, they will be able to consolidate the list of recommended oils for their vehicles to just 1 - any oil meeting the "dexos 1" specifications.

Current & Future Dexos Testing Requirements

The youtube video displayed below is one that was taken from the 17th Annual Fuels & Lubes Asia Conference. It's a little tough to hear, but not impossible. For some reading this article, it may be a bit more technical that what you need, but for those who are interested, it provides a good rundown of the testing requirements for dexos 1 and 2 motor oils and future tests being considered.


Dexos 1 or Dexos 2? What's the Difference?

In truth the difference is relatively simple. dexos 1 oils are for gasoline engines and appear to be primarily aimed at the North American vehicle market. dexos 2 licensed oils are for diesel engines (and for European gas powered engines). Often dexos 2 licensed oils will meet API gas engine specs such as API SM, so you may be able to use a dexos 2 licensed oil in a gas engine, so long as it meets the requirements for your application.

What About Other Makes?

Can you use dexos oils in vehicles of other makes outside of GM?

Well, the answer to that question is "Maybe". Again, dexos 1 oils will meet the ILSAC GF-5 spec, which is basically API SN with the "Resource Conserving" designation. So, if you own a vehicle that calls for API SN, ILSAC GF-5 or earlier specification (and requires no other OEM specific specifications), then you could use a dexos 1 licensed oil, as long as the viscosity is a match.

Unfortunately, many newer vehicles from other makers are calling for 5w20 or 0w20 motor oils, which are not yet a part of the dexos 1 licensing scheme - only 5w30. So, in those cases, if you go with a dexos 1 licensed 5w30 oil in a vehicle that calls for 5w20 or 0w20, you could cause yourself problems - even if only when dealing with service centers that will balk at your choice of viscosity.

It's of little consequence, though. If you're looking for dexos 1 quality for your non-GM vehicle, just go with a high quality synthetic oil. You'll be getting all the protection and performance you need, every bit as good as any dexos licensed oil. Just know that when I say a "quality" synthetic oil, that is not a term that I would apply to ALL "synthetic" oils.

Use the free motor oil comparison service offered on this site to do a thorough comparison of motor oil specs before making any assumptions regarding the quality of any one brand of oil, synthetic or not.

Get Out Your Checkbook

Of course, the "cover charge" to get into the exclusive "dexos 1" club will be considerably higher than attaining the less exclusive API licensing. These additional costs are not only due to higher licensing fees ($1,000 per licensed oil plus 36 cents per gallon sold), but are also attributable to the higher cost of developing the oil in the first place.

The "dexos 1" spec will be relatively rigorous, designed to enhance engine protection AND engine oil longevity. As a result, for an oil to meet the "dexos 1" spec, it will likely be necessary for oil manufacturers to utilize primarily Group III and/or Group IV basestocks in the formulation, certainly adding considerably to the cost of the oil, thus raising the price for the end user. In essence, primarily synthetic oils and high quality synthetic blends will be able to meet the spec.

Additionally adding to the cost of the oil will be the inclusion of molybdenum in the spec for it's anti-wear properties. Although ZDDP is extremely cheap (and effective) as an anti-wear additive (while also working as an anti-oxidant in the oil), molybdenum is incredibly expensive (in the order of 50 times more expensive) and does NOT also act as an anti-oxidant - thereby requiring the use of additional additives to serve the purpose.

Dexos 1 Production Costs Higher Too

Moreover, the costs to produce "dexos 1" oils will also be higher as the result of additional testing costs to make sure that the oil actually meets the "dexos 1" specifications. And, lastly, costs will be higher since there does not appear to be a flexible interchange mechanism in place to allow oil manufacturers to purchase "dexos 1" licensed additive packages or basestock blends from various different suppliers (which ordinarily would provide for additional competition and a lowering of additive package and basestock prices).

Lube Industry is Not Happy

There are numerous reasons for companies and organizations within the lube industry to be less than thrilled. API, of course, is contemplating the possibility that API licensing could be phased out altogether if North American OEMs begin moving to their own, proprietary specifications. That is unlikely, but possible.

Lubricant manufacturers are looking at things from a slightly different perspective, although still not entirely positive. For them the question becomes which classification system to stick to. Should they be manufacturing their oils to meet API specs or "dexos 1" specs? Of course, for specialty companies that produce mainly premium synthetic lubes, this may be less of an issue. Chances are their oils are already positioned well to meet the new "dexos 1" specs, which will likely mean they will easily meet API and ILSAC classifications as well (unless the "dexos 1" spec ends up conflicting with API or ILSAC classification requirements).

Quick lube owners & operators are none too happy about the prospect either. If "dexos 1" does go into effect, it will likely mean additional stock requirements which can be a real headache when space is limited and mix-ups can occur. However, there may be a way out...

Magnuson Moss

As it turns out, there are some who are crying foul and are referring to the Magnuson Moss Warranty Act as justification for barring GM from even having the option of introducing "dexos 1". They contend that this would be a violation of the Magnuson Moss Warranty Act which states that, if an OEM requires a particular product to be used in order to maintain a warranty, the product must be provided for free (unless the company is able to PROVE the necessity of using this product for proper operation).

Although I'm certainly not a lawyer, I'm not entirely convinced that this would apply. GM is not requiring the use of a particular brand of product, but only an oil that meets their specification. Generally, the Magnuson Moss Warranty Act is designed to protect consumers from OEMs that might try to void a warranty or deny a warranty claim unjustifiably based on the customer's use of the "wrong product" to maintain their vehicle (or other product). It's also designed to keep OEMs from bilking customers by requiring them to purchase a "house brand" product in order to maintain their warranty, thereby forcing the customer to purchase what is often an overpriced and generally useless product when there is no justifiable reason for doing so.

Again, I'm not sure this scenario falls under the auspices of the Magnuson Moss Act. But, the lube industry has the clout and the money to place leverage against the introduction of "dexos 1". Only time will tell if they have ENOUGH clout to get their way. Introduction of the new GM spec is scheduled to coincide, almost exactly, with the introduction of the new ILSAC GF-5 requirements. So, we'll see how this all plays out. Stay tuned ...

The Story Continued

Well, since this article was originally published, GM's Dexos 1 (and 2) specs have gone into full force and many oil companies are "paying the piper" to make sure they have oils to meet these new specs for GM vehicles. Of course, consumers are paying the price as well, since motor oil manufacturers are simply passing the bulk of the additional expense on to consumers.

The question is, are consumers any better off for it? Are their vehicles actually going to last longer? Are they going to see an appreciable increase in fuel economy? Only time will tell on that front. I think it's probably safe to say that there won't be a significant fuel economy benefit for consumers. Increases in fuel economy will be negligible and probably undetectable for vehicle owners, although the increases will possibly be enough to make it worth it for GM, so as to put them into better position to meet government mandated CAFE standards.

In the end, since Dexos 1 & 2 oils will fully meet/exceed current API and ILSAC specs, you won't likely be any worse off for performance and protection with these new Dexos oils, just a little lighter in your pocketbook.

Want to now who's currently licensed? Check it out at GM Dexos 1 Licensing

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