20w50 Semi Synthetic Racing Oil 3 x 5 Quart

The 20W50 Semi Synthetic Racing Oil 3 x 5 Quart by Lucas Oil is designed for drivers and mechanics who demand maximum engine protection under extreme conditions. This product comes in a bundle of three 5-quart bottles, providing a total of 15 quarts of premium racing lubricant. It is ideal for high-performance street builds, track applications, and vintage muscle cars where heavier oil viscosity is critical.

This semi-synthetic formulation balances traditional mineral oil durability with synthetic additives for superior thermal stability. A 20W50 viscosity grade delivers robust film strength across wide temperature swings, ensuring cold-start pumpability and maintaining pressure and protection at sustained high RPM and elevated engine temperatures. Lucas Oil's semi-synthetic base resists oxidation and viscosity breakdown, making it suitable for carbureted engines and flat-tappet cam conversions.

Mechanics and performance enthusiasts select this product for engines that cannot tolerate lighter synthetic oils, including vintage small-block engines. The formulation includes anti-wear (zinc/ZDDP) additives essential for flat-tappet protection, detergents to control sludge, and anti-foam agents to preserve oil circulation efficiency. This makes it a trusted choice for a variety of racing applications.