Duramax Semi-synthetic oil

[jake75]

For $19 I bought a "Groupon" for a LOF and tire rotation at a well respected local chain of auto maintenance shops.
The invoice indicated they used Duramax Semi Synthetic 5x20 item #26-520. Looking on the internet it appears that is a GM product intended for diesel engines.
Anyone familiar with this oil?

[ColonelPanic]

Whether this is actually a diesel oil or just bears a name similar to the engine, I don't know. It could be just a standard 5w20... Details on it seem to be scarce online, and there's too many results regarding the Duramax diesel itself.

From what I can tell, according to this it seems to be a Warren Unilube product. They package a variety of house brand oils.

They appear to be making the Meijer brand oil, which I have been using lately. I have their conventional 5w30 in the Vibe and Accent, and 10w30 synthetic in my mower and generator. Haven't had problems with any of it.

[jake75]

Their normal price for LOF and Tire Rotation is $39.95 so I was surprised to see that were using a semi-synthetic at that price point. I bet they buy it in 55 gal drums at a very good price. I suspect that the cost to manufacture semi-synthetic is not very much more than regular oil dino oil. Also -maybe a a 95 dino oil and 5 synthetic can be called "semi-synthetic" (sort of like the claim of "Made with Real Cheese" on Cheetos). WIKI says semi-synthetics have a max of 30% synthetic.