Smaller Wear Scars = Better Protection

The four ball wear test will give a good indication of how well an oil will protect your engine. The smaller the wear scar, the better the protection.

One thing that you may notice is that the following tests were not all performed using the same pressure, temperature or rpm. This is because each oil is designed for a different type of application. As a result, the oils are each tested under conditions that most closely match the application for which they will be used.

You may also notice that the oils being compared are not always of the same viscosity grade. Bear in mind that the oils are generally being compared to those that would be their most likely competitors in the lubrication marketplace.

For instance, in one of the charts below AMSOIL Series 2000 0W-30 is compared to viscosity grades of 5W-50 up through 10W-30. This is because very few companies actually have a 0W-30 motor oil. Mobil 1 0W-30, although not shown on this chart below, scored a .60 mm wear scar.

Since, AMSOIL's 0W-30 is recommended for the same applications that the comparison oils would be recommended for, it makes sense that these are the best oils to compare it to.

Many people still have the notion that a higher viscosity oil will protect better than a lower viscosity oil. This is not necessarily the case as you can see in the wear scar test comparing the 0W-30 to other "heavier" viscosity grades. The quality of the oil you purchase will have much more effect on the protection benefits of the oil than will the viscosity grade (although choosing the correct viscosity is still important).

Moreover many people still falsely believe that the number preceding the W in a multi-viscosity oil refers to viscosity. This is simply not true. This number is only a relative indication of winter weather performance and is really only an indication of how quickly your critical engine components will receive oil on a cold winter day. The lower the "W" number, the better the cold weather performance. The number after the hyphen (-) refers to the viscosity of the oil at operating temperature.

With that said, looking at the numbers, I think that it is clear to see who comes out on top, no matter what viscosity oil you are looking at. In every one of the following graphs, AMSOIL beats out all of its closest competitors - normally by a fairly wide margin.

There just really is no comparison. I think that it is clear which oil you should choose if you want superior engine wear protection - AMSOIL!