Do Car Manufactures Test Their Recommended Engine Oil?

Do Car manufactures make their own oil? eg Genuine Toyota Engine oil, and if yes do they actually test their oils which they recommend for their cars? Or do they just get some oil from other manufactures such as Castrol and Valvoline and re brand them as their own with or without testing?





Thanks in Advance, PigeonKickerDo Car Manufactures Test Their Recommended Engine Oil?
Current oil available on the market is API/SM. As Damitis... mentioned you do not have to use the OEM oil. Just an oil that meets the API standard that they use. Even Wal-Mart Super Tec oil meets the standard and will not void the warranty.


Now for the ones driving older cars your API standard may be as quoted earlier as SF/SG and you can only find SM don't worry, this new oil exceeds the standards that your car required and works just fine. Plus it is the only one you will find on the market.Do Car Manufactures Test Their Recommended Engine Oil?
To preserve your warranty, use OEM oil.


Contrary to the 1st poster, some company do sell their oil to be re-badged, this is not unusual at all.


While I don't see Ford, GM, Chrysler, Toyota or the others investing in refineries and facilities simply to make oil for their cars, it is possible.


Its more likely that the oil they sell is made by someone else and re-packaged as it meets or exceeds all the manufacturers specifications.
You do not have to use OEM oil by name but you MUST use oils that meet viscosity levels set by the OEM and meet other standards(additives) such as SF,SG oils etc etc. By law you do not have to use a OEM product but the product you use must meet specications or your warrenty could be void in the event of a failure if they test the oil. Once in a while they will send off a sample to be tested. By the way I work for Toyota. All manufactuers have oil packaged by another company and put their name on it. I have yet to see a Manufactuer that has their own refinery Sometimes if you look on the back of an oil bottle near the bottom (fine print ofcourse) they will have the name of the company that refined the oil.
hard to say, but you'd hope that they'd want to preserve their reputation by checking to make sure. Rebranding someone else's work is generally dishonest, and is heavily punished in the business and academic worlds.