Some on the TJ site have asked about "what oil to use?" Should be simple, one would think.
Well, they managed to confuse the selection of antifreeze in the recent past, now motor oil is next. GM is going for its own special recipe motor oil, most likely derived from Group lll and lV base stocks (synthetics) and most likely in 5W-20/30 grades.
There has been some bashing about of this on BITOG
and there is an article in Jobbers World
as follows (in part).
Castrol advised its marketers that during October 2010 Castrol Edge 5W-20 / 5W-30 and Syntec 5W-20 / 5W-30 will transition to exceed the requirements of GM's dexos1™ specification. At the same time, it says "While the decision has been made not to officially license Edge and Syntec, Castrol will guarantee their performance in GM gasoline engines that recommend a dexos™1 approved engine oil."
Although Edge and Syntec will not be officially licensed as dexos1™, Castrol says, "Edge 5W-20 / 5W-30 and Syntec 5W-20 / 5W-30 will have passed all the testing requirements of the dexos™1 specification and will provide the required protection and performance when used in applications requiring a dexos™ 1 approved engine oil."
In addition, Castrol says,"Syntec 5W-20 and 5W-30 will be dexos™1 capable under a new name yet to be officially communicated."
When asked: If a dexos1™ license engine oil is not used in an engine that calls for dexos1™, will the warranty be voided?," Castrol says, "No." They continue by adding, "In order for the warranty to be voided, the engine manufacturer must prove that the engine oil caused the failure. If the engine oil meets / exceeds the requirements of dexos™ 1, the warranty can not be voided just because the engine oil in question is not officially licensed."
Heres an interesting article @ http://www.ascca24.com/newsletter/oildexos04.19.10.pdf
The term “Synthetic” is meaningless in North America. - Shop owners and consumers alike assume that this term indicates superior quality. But, it is increasingly used as nothing more than a ploy to lure un-educated buyers into products that inflate oil company profits without a corresponding benefit to the consumer. This could result in a compromised reputation and liability for the shop owner. The GM dexos1 approval will offer assurance of the type of quality that is expected of a “synthetic” product. Informed shop owners will ignore the term “synthetic” and look for dexos1 approval instead.
Quaker State has a Dexos 1 certified product already @ Quaker State | Quaker State
So have Pennzoil and others.
Actually, motor oil has been a bit confusing of late, especially with regard to synthetics, and what GM is doing is simplifying the quality requirements for their vehicles. The problem is that other vehicle Manufacturers will start doing the same thing, like in Europe. Antifreeze confusion all over again, but with oil this time. Looks like we need a new industry standard.
The additional improvements, so they say:
- Engine cleanliness
- Corrosion protection
- Sludge control
- Wear protection
- Aeration control
- Fuel economy