Liqui Moly’s Synthoil Premium 5W-40 Synthetic Motor Oil is one of the most popular engine oils used in high-performance German and European vehicles. It is almost similar in specifications to Shell’s Rotella T6 except that Synthoil Premium can be used on both diesel and gasoline engines. Synthoil Premium comes with amazing viscosity properties across a wider temperature range, providing excellent protection in hot weather and one-click engine starts in cold temperatures. But with German technology behind its formulation, Synthoil Premium is perfect for reducing metal friction points, giving you at least 15,000 miles in between servicing. Vehicle owners who have used Synthoil Premium can also attest to the difference in engine performance it makes.