Yes, Idemitsu has discontinued the Zepro line engine oil and replaced it with new Idemitsu SP/GF-6 oil since last October.I noticed just lately that Idemitsu has dropped the Zepro line. As for Kirkland oil, it’s decent and blended by Warren Distribution who also blends Supertech. Most likely the same oil.
In US, dealers will use whatever the cheapest bulk oil they can find. Car manufactures can’t do anything to force them using OEM oil exclusively. I believe it’s your dealer’s own decision to use Idemitsu and unknown synthetic blend oil (for which Mazda engine?). Not all Mazda dealers are going to do that.I have also read that Mazda dealers are going to Idemitsu exclusively for their synthetic oil changes. It used to be Castrol or whatever the dealership decided. My dealer told me they use Idemitsu for synthetic and another brand for Syn blend. They wouldn’t say who.
Brand name is still a big factor for most consumers.What's the consensus on Kirkland 0w-20, it's got all the ratings you could wish for, and in independent tests it comes out quite good, and it's made by Warren Distribution Inc ...
And the price is also right
@escape75 the consensus as you have already eluded to is the Kirkland oil complies to the standards it should, and performs well in a variety of conditions. It is safe to use even if not a "brand name". Remember if you are not satisfied with a product you bought from Costco, they will take it back (I think this would include motor oil since they return christmas trees).
The Costco return policy is so generous that abuse of it has been the stuff of legend. We’ve all heard of people trying to return a broken printer Costco hasn’t sold for eight years. Or trying to r...thekrazycouponlady.com
I prefer name brand oils. .... So I stick with companies that have established a good reputation over the years, Pennzoil, Mobil, Quaker State, Valvoline, etc.