PSC's Heavy Duty Fleet and Off-Road Equipment Lubricants refined by their SAE weight category allows users to refine their search starting with the oil's weight as determined by the Society of Automotive Engineers better know as SAE.
The SAE weight is only the thickness of the oil and is a good starting point to refining down the correct lubricant for your application.
For a more detailed explanation of a lubricant's viscosity you can read our Blog: