KIXX Geartec GL-4 SAE 80W-90 / 90 / 140 by GS Caltex is a high-quality, mild extreme-pressure (EP) automotive gear oil formulated to deliver reliable lubrication and protection in manual transmission and gear applications requiring API GL-4 performance. Manufactured from highly refined base oils and a balanced additive system, it ensures smooth operation, enhanced durability, and long service life under a wide range of operating conditions. The specially designed sulfur-phosphorus mild-EP additives provide excellent load-carrying capability while remaining non-corrosive to sensitive copper and brass components found in synchromesh systems. Its superior thermal and oxidation stability helps keep gear cases clean, prevents sludge formation, and maintains consistent performance over extended drain intervals. Applications: Automotive manual synchromesh transmissions and transaxles (where GL-5 is not recommended) Spiral-bevel and worm gear differentials Automotive steering gears Tractor and agricultural gear systems Oil-lubricated track rollers of crawler equipment Industrial gear units requiring API GL-4 lubricants