I'm thinking about using Chemlube 751 or 501 , the 751 is sae 40wt. and the 501 is sae 30wt. I'm getting my new compressor this week and want to start off on the right foot with the right oil . Does anyone know what ISO the oil should be ? Thanks and sorry to open this can of worms again but there are a lot of different opinions . I think I would be OK using a good synthetic made for high pressure compressors but let me know what you use.