Would you use this full-synthetic oil in your Ascent or other Subaru? That works out to $2.50/qt which is an outstanding price. Of course, you have to be a Costco member. Warren is the manufacturer of this full synthetic oil.
This oil is blended by Warren Distribution which is a premier supplier of private label lubricants and related automotive chemicals in the US. They also blend synthetic oil for Walmart and Amazon, both of which have proven to be excellent oils. There have been multiple discussions about this new oil offering from Costco on many forums. The overall consensus is that this should be an excellent oil that exceeds what's required for most vehicles. Some people have already had it analyzed and the results were very favorable.
This oil is also certified for API SN PLUS, the new motor oil specification for turbocharged engines.
Is this oil better or worse than typical premium synthetic oils? It appears to be very similar. Is it the best synthetic oil you can buy? Probably not, that award still goes to Amsoil and Pennzoil Ultra Synthetic. However, it appears to be the best oil you can buy for the money.
Would I use in my cars? Yep, my Forester is running it right now. Am I running it in my Ascent? Nope, I'm using Amsoil which costs a helluva lotmore, but if I wasn't so damned particular I would and I have little reservations that this is probably an excellent oil and certainly an incredible bargain.
Costco is one of the few wholesalers worldwide with the buying power to offer a premium oil at such prices. Keep in mind that Costco makes the majority of their profits from their memberships dues (believe it or not) and sells products at a very low 11.4% profit margin or less which, along with their massive buying power, is how they can offer such incredible bargains as this.
Additionally, Costco considers their Kirkland name brand a trustworthy premium brand and they very carefully vet any product that contains this brand. Many Kirkland products are manufactured by name brand companies and sold for considerably less by Costco under the Kirkland brand.
As with all automotive engine oils, many people will have many diverse opinions, but I do believe that this is most likely an excellent oil at an incredible price. You can buy better oil but you won't find a better bargain for what you receive.
Yep. I'd run it. The manual calls for SN, but SN Plus is "new and improved!"
"API SN PLUS is a new motor oil specification developed for turbocharged engines that is being developed in response to automakers request for motor oils that protect against Low-Speed Pre-Ignition (LSPI). LSPI is an engine condition known to occur in Turbocharged Gasoline Direct Injection (TGDI) engines that can be mitigated by changing the motor oil formulation."
I'm a Costco fan and would buy that oil no question when I need to replenish my "emergency stash". (I don't do oil changes, but do keep a little around just in case it's needed, especially for the MY11 that my younger daughter drives)