Originally Posted By: dlundblad
Originally Posted By: WhizkidTN
Over on the Kia/Hyundai forums/FB pages, there are many who run T6 5W-40 but who don't understand that this oil is
not for gas engines and is NOT recommended by Shell to run in our DI turbo engines (many have asked). It's just a bad idea and due to the very different add pack in it, can lead to deposits and sludge (lots of fuel dilution and blow-by in our engines). It does NOT meet Kia's up-to-date oil requirements published in a TSB and I think might very well result in denied warranty claims.
In the RIGHT application, I'm sure it is a great oil!
Per Shell, it carries gas approvals.
http://rotella.shell.com/products/t6-ful...t6-brochure.pdf
Hyundai is very lenient with their oil specs so honestly I don't see there being an issue with running an API SM xxw40 oil.
Where do you see "gas" approvals in that T6 PDF from Shell?
It does have Diesel approvals but not gas ones (please correct me if I'm wrong).
Additionally, on those aforementioned Kia/Hyundai forums, they talked directly with a Shell Chemical Engineer and he flatly stated it was not for our gas engines and recommended several other Shell products.