The only way to know for sure that it is CI-4 is if it says CI-4. All Delvac 1 made today is CI-4. You probably bought old stock. There was a transition period where Mobil claimed that the oil labeled CH-4 was actually CI-4, as if they were using up a surplus of containers. If you can you might return it . If you are having troubles finding Delvac1 labeled CI-4, I know AVLube has it in stock as I just recieved a case od Delvac1 from them today.
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