In the 1930s, automotive engineers faced a crisis: as engines became more powerful, gearboxes were literally destroying themselves. The problem wasn't the metal—it was the oil. Traditional lubricants simply couldn't handle the extreme pressures where gear teeth meshed, leading to catastrophic wear and failure.
The breakthrough came with Extreme Pressure (EP) additives containing sulfur and phosphorus compounds. Under intense heat and pressure, these additives chemically react with metal surfaces, creating a protective sacrificial layer that prevents metal-to-metal contact during those crucial microseconds of gear engagement. This discovery revolutionized transmission technology, allowing vehicles to handle exponentially higher torque loads.
Today's GL-5 specification oils build on this chemistry. Hexol Torsion 80W90 combines modern EP technology with anti-wear and anti-foaming properties to protect differentials and gearboxes under mechanical shocks—a direct descendant of that 1930s innovation.
