This is the factory-specified 80W-90 GL-4 gear oil for the Beemotor TEV rear-axle spur-gear reducer. The TEV maintenance manual requires 1.5 L per fill, with the first change at 2 months / 2,000 km and subsequent changes every 6 months or 5,000 km. Using the correct viscosity grade protects the reducer gears and bearings against wear, corrosion, and thermal breakdown. Each bottle contains exactly 1.5 L — one full service fill. For operation below −26 °C, switch to the corresponding winter-grade variant. Never mix with other oil brands or grades.