Oil-lubricated air compressors need oil to help cool the cylinder head and prolong the compressor’s life.
When working with a 20-gallon air compressor or larger, it will likely be a splash lubricated oil system.
These compressors require you to change the oil at regular intervals.
How Often Should You Change Your Compressor’s Oil?
The compressor will need an oil change every 400 hours when using conventional oil. With synthetic oil, you need to change it every 1,000 hours.
Always defer to your compressor’s operating guide for the most accurate oil change requirements.
So often, we only use our compressor infrequently, and we forget to think about the oil requirements.
Additionally, when we rarely use the compressor but leave it plugged in, the compressor will still cycle regularly to keep the tank full.
This adds hours to the oil and increases the frequency when it will need to be changed.
Turning off the compressor when it is not in use can extend its life.
What Is Air Compressor Oil?
Compressor oil is generally either a conventional or synthetic oil.
The difference between engine oil and air compressor oil is that compressor oil has no detergents.
While detergents can help clean an engine, those same detergents can cause the oil to carry metal shards into the cylinder wall of your air compressor.
Generally, your compressor will perform better if you use precisely formulated air compressor oil.
However, you may find yourself in the off-hand situation where you need to add oil and don’t have access to air compressor lube.
What are some alternative oils that you can temporarily use that might get you by?
Thin Hydraulic Oils
Hydraulic oil is similar to compressor oil in that it does not contain detergents.
Any 20-weight or 30-weight hydraulic oil should make a good compressor oil alternative.
If you are working outside in extremely cold weather, you should go with the thinner 20-weight oil to make sure your compressor will start more easily.
However, for most climate-controlled shops, a 30-weight oil is a good, year-round choice.
Hydraulic oils tend to have some sealant compounds in them and work well for oiling, cooling, and preventing your compressor’s internal rusting.
ATF Oil
Automatic Transmission Fluid oil is another one that we see being used in compressors.
The transmission fluid seems to hold up well to the heat and the loads that air compressors create.
While most ATF fluids have some detergents in them, they are designed to go long distances without being changed. This makes them better suited for use in compressors.
Transmission fluid has emulsifiers to help it handle the condensation that can build up inside a compressor head.
You should be careful not to mix oil types if there is a different oil in your compressor; empty that before adding transmission fluid.
Also, be aware of warranty concerns. Some brands are very restrictive on which oils you can use during the warranty period. If you add the wrong brand or type of oil, it can cause you to void your warranty.
Compressor Oils
My favorite option is to use a dedicated compressor oil. This seems to deliver the best results.
Compressor oils do not cost much more than engine oils do. It may be cheaper than some of these alternative options that we discussed.
You’ll have the peace of mind that you are adding the correct oil.
If you can find synthetic oil, that is the best idea. Synthetic compressor oils can go up to 1,000 hours between oil changes. For the heavily used air compressor, this can save you a lot of time in maintenance.
Can You Use Motor Oil In An Air Compressor
It is possible to use a standard weight motor oil in your compressor.
While this isn’t the top recommendation, it could get you by.
Generally, it is not recommended to run a multi-viscosity oil in a compressor since it might cause foaming issues.
Sticking with a 20W or 30W oil is your best choice. In cold weather, consider a 10W oil to make it easier to start the compressor.
OEM Lubricants
Original Equipment Manufacturer lubricants are always the best option.
Just because I’ve used the wife’s Crisco to dip the threads on the screws of my home project does not mean that I should do the same for my clients.
When you are a professional contractor, it is best to choose a lubricant that meets the original equipment manufacturer’s standards.
Sometimes you will use the oil made by one manufacturer in a different machine. It is often fine to use a Campbell Hausfeld oil in an Ingersoll Rand air compressor. This is especially true when working with small air compressor brands who might not manufacture their oil brand.
What Is The Proper Viscosity Of Air Compressor Oil?
For most conditions, a 20W to 30W oil is the ideal solution. I’ve heard of some home contractors who used a 0W-10W oil in their machines for working in the cold winters of Minnesota.
Very few contractors will need to take these drastic measures.
Is Air Compressor Oil The Same As Air Tool Oil?
Air tool oil is generally thinner and contains anti-rust blockers.
While you might be able to run a dab of compressor oil through your air tool, you will not want to put air tool oil into your compressor.
Air tool oil is too thin to support the demands of the compressor.