I bought some of the Haynes silicone grease that was recommended in one of the write ups for the GXCS4 and my compressor started making some weird noises when I used it, so I cleaned all of it out and ordered some grease from Renewable Lubricants, it's supposed to be the grease that's recommended for Omega compressors...seeing how the Omega compressors have a lot of the same components that's on the CS4 leads me to think they are both made in the same factory. I got the new tube of grease today and used it in the CS4 and it definitely sounds a lot better now. This is just my opinion and take it for what it's worth....I think the Haynes silicone grease is too sticky for using in these compressors, the Renewable Lubricant grease is a different consistency and I think it does a better job lubricating this compressor.........