You can always count on Royal Purple’s 51520 SAE 5W-20 High Performance Synthetic Motor Oil to give you better wear protection, superior corrosion protection, and increased fuel efficiency. The latter is achieved through Royal Purple’s unique formulation that comes with low coefficient of friction. Its blend of additives also help protect your car’s catalytic emissions system while also helping prevent lubrication starvation and the formation of sludge which typically occur on ethanol-based fuels. Its Synerlec additive is what makes Royal Purple extra special. This additive works at the molecular level to give your engine the kind of performance it needs. Royal Purple can also be used to top-off other types of oils without the need to drain existing engine oil.