Engine oils have multiple formulations developed by oil suppliers to cover the vast majority of equipment engine requirements. You generally do not need to add anything to the formulation of the oil unless you have a very extreme engine condition. Even then, it’s best to consult with your equipment manufacturer and oil supplier before introducing any oil additives into your system.
If you decide to DIY a solution for your specific need on your own and include additives, you’re doing so at your own risk. You may solve one specific issue or enhance a certain property, but you likely will negatively impact on others such as hindering the oil from dissipating heat or from forming deposits.
Example: Extreme Pressure (EP) Additives
EP additives are often considered as a possible solution for situations where engine wear is a concern. However, EP oil additives are generally used in gearboxes and do nothing until they’re in a tight load zone where the pressure is extreme. At these points, the EP additives turn from a liquid to a solid to protect the gears.
While this is great for gears, if added to an engine oil, it can crowd out other necessary additives that may be required by your engine. In an engine, the EP additive can usually be found at the piston ring/cylinder interface or cam shaft. At these locations, loads are not high, and clearances are small. The EP additive will not activate because of the low pressure and crowd out the anti-wear additives. EP additives in these situations could actually cause an engine to seize.
Reasons to Avoid EP Additives in Engine Oil
Using an engine oil that has a high rating or was tested for EP additives is not a good solution to engine wear and could cause problems down the road. Some of the reasons we recommend avoiding this additive include:
- The sulfur or chlorine compounds contained in EP additives can react with water and combustion by-products, forming acids that facilitate corrosion of the engine parts and bearings.
- Bearings, coolers and other components are typically made of a soft metal, like copper. The sulfur compound found in EP additives will attack the copper in components causing failure.
- While lubricant technical data sheets may reference the Timken OK Load test and indicate the oil was tested for EP additives, this test is used primarily to test gearbox lubricants. This test should not be used as a guide to determine if EP additives are beneficial for your specific engine oil use-case.
You don’t need EP additives
Engine oils are formulated like they are for specific reasons. Work with your equipment manufacturer and oil supplier to make sure you have the right oil for your application. Not only will your oil supplier help you spec out the right oil, but they’ll be also a fountain of information on what to look out for and provide solid recommendations.