Automotive Engine Oils: How To Read The Label.

Welcome to the first edition of OILY Academy!

We will be focusing on how to read and understand the label of an automotive engine lubricant.

Most of us know the market trends on the different viscosity grades, some of us even read the equipment manual to select the correct lubricant for the application. Whatever the case may be, it is important to know what the information on the product label tells us about the lubricant inside the bottle.

There are four important things to learn from the label of engine oil:

  • What is the viscosity classification of the lubricant?

  • What is the performance level of the lubricant?

  • Is the lubricant approved by any OEM’s?

  • Exhaust After Treatment Compatibility.


The most important thing to look at when choosing a lubricant is viscosity.

For this reason, the Society of Automotive Engineers (SAE) developed the original SAE J300 viscosity grading system for engine oils back in 1911. This system makes it easy for the general public to choose a lubricant with the correct viscosity. There are two categories of engine oils with regard to viscosity. There are mono-grade oils, also known as summer oils and they are only suitable for work in higher ambient temperatures. These mono-grade oils are most efficient once the equipment reaches its optimal operating temperature. Today most engine oils on the market are multi-grade oils which means the lubricant can operate in both high and low temperatures. The SAE has therefore devised two separate viscosity measurements, one for high temperature (100 ゚C) which indicates high operating temperatures and the other for temperatures as low as - 40 ゚C, which simulates cold start temperatures. The cold temperature viscosity grade will be indicated with the letter “W” for example 0w, 5W, 10W, 15W or 20W. The cold temperature viscosity grade will be followed by the high-temperature viscosity grade 20, 30, 40 or 50 as seen on the API stamp below. The most popular multi-grade viscosity classifications are SAE 15W-40, 5W-30 and many others.

Performance Level 

There are quite a few performance classification standards, ASCEA, ILSAC, and most commonly foun