1L Bottle of Yamalube SAE-90 GL4 for outboard motors up to 150HP (use GL5 for 150-425hp)
Yamalube GL4 gear oil provides specialized anti-wear, anti-corrosion, and anti-foaming protection tailored for Yamaha marine lower units and scooter transmissions. It maintains a stable oil film under heavy loads, prevents thermal breakdown, and safely protects soft yellow metals like brass components from sulfur corrosion.Key Protective BenefitsCorrosion Resistance: Fights rust and oxidation in wet marine or high-moisture environments.Extreme Pressure Load Capacity: Handles heavy gear-to-gear forces without losing viscosity or thinning out.Foam Control: Minimizes air bubbles to ensure constant, uninterrupted lubrication across gear teeth.Safe for Synchronizers/Yellow Metals: Formulated with balanced additive levels that avoid the aggressive chemical erosion associated with some high-additive GL5 oils