Originally Posted by rileyc
I received a response from Mobil Marketing re: Delvac 1300 Super HDEOs being synthetic blends. Effective July 1, 2019 Mobil Delvac 1300 Super HDEO is officially being marketed as a synthetic blend, and Mobil Delvac Extreme as a synthetic HDEO.
Since there are no official API guidelines regulating the percentage of synthetic base stock used in synthetic blend motor oils, there is no way to tell how much synthetic base oil is used in Delvac 1300 Super. Mobil Delvac 1300 Super has its share of critics here on BITOG, especially after Shell's allegation that the oil failed the Volvo T-13 oxidation test. However, it's good to see that Mobil is improving the formulation of Delvac 1300 Super, albeit incrementally.
I've also noticed on Mobil's website that Delvac Super 1300 15W40 and 10W30 are now listed as semi-synthetic oils.
I recently switched back over to Delvac Super 1300 15W40 in my Pre-EPA Detroit Series 60 engine. I bought a couple of gallon jugs of 1300 15W40 at a Walmart in Childress, Texas about a week ago. It's currently marked at just under $11.00 per gallon.
Although "Semi-Synthetic isn't listed anywhere on the labels of the jugs I just bought.
Does anyone have any idea how to decipher Mobil's production codes? I'm curious to find out if the semi-synthetic version has hit the store shelves yet.
BTW, regardless if the jugs I bought are conventional or semi-synthetic, doesn't make a difference to me. I used CJ4 Delvac Super 1300 15W40 for the first 150,000 + miles, and my UOAs always looked very good.
I'm hoping they don't do a price-hike on the semi-synthetic labeled Super 1300 product.