The ad says "Delvac, M1 Truck Diesel or Blue jug". They claim you can order online and pickup in store, but when you click you get a generic jug "Valvoline/Mobil" added to your cart.
I would go to the store and let them scan the jug; if it does not come up with the $12.99 price I would push the issue. The Mobil 1 TDT is definitely synthetic, and I have used it in the OM602; will not hesitate to use it in the OM606 either.
The sale is on until 24 December.
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