We have a Sam's Club air compressor in the barn to run the air gates in the milking parlor, it is about 15 years old now. I seem to remember that the last time I changed the oil I used Mobil 1, didn't write it down, so I'm not sure. Motor started bucking today, took the motor off and into repair shop, so it's a good time to change the oil again. Main Man says that compressors need non-detergent oil.....I think that would probably be fine, but I don't have any here, now. I am going to use some 0-40 synthetic motor oil. If someone on here convinces me that I am going to have a disaster by doing so, I can drain it out and put in something else.

So, how about it? Would the detergent in motor oil hurt an air compressor? I don't see how it could, but I am willing to learn.