Richard Smith wrote:

"Pete C." writes:

Joe AutoDrill wrote:

Also, there's nothing special about compressor oil--the overwhelming
majority will be perfectly happy with straight 30 wt non-detergent just
like is used in lawnmowers etc, just don't use the wrong weight ( or a
multi viscosity oil ) because the oil distribution system is based upon
known oil properties as well as crankshaft speed.

...My big 3-phase monster takes Mobil-1 10W-30 Synthetic. Which Dayton
charges $29 per quart for or something like that.

You can't imagine how ****ed off I was when the UPS package showed up with
my compressor oil and it was Mobil-1 off the shelf of the auto parts store
at that price...

Ouch. Mobil-1 is definitely good oil though, I use it in most
everything.

I've heard compressor-oil is low-ash and - well, something to do with
compressors have a high "compression ratio" and can make a mess of
ordinary engine oil - or even run as a diesel engine combusting the
wrong crankcase oil.

The current diesel rated oils are "low ash" as a result of diesel
particulate filters on current emissions controlled diesels. I use
Mobil-1 5W40TD in my diesel truck and also in my diesel tractor.