Is there any reason why I can't use 10W30 synthetic oil in a Harbor Freight McGraw 20-gallon air compressor. It calls for 30 weight non detergent oil.
Seems like overkill but if it makes you sleep better at night rock on.I think I will get a bottle of Royal Purple synthetic compressor oil in 30 weight and use that.
Mine has never turned milky looking, I have M1 0W-40 in it, and have for about the last 10 years.If you put detergent motor oil (like what you'd put in your car) in your air compressor, it will turn milky looking. You want to run a non detergent oil. For home use, it doesn't matter if it is conventional or synthetic.