10 Best 75w140 Synthetic Gear Oil of December 2025

• Formulated to maintain excellent low temperature fluid protection
• Helps provide outstanding thermal stability for cleanliness and longer service life
• Contains special additives to assist in protecting gear teeth from rust and corrosion and reduce chattering in limited-slip differentials
• Recommended for conventional and limited slip differentials and non-synchronized manual transmissions where API GL-5 or API GL-4 fluid is specificed

Valvoline

Amsoil

• Greater wear protection for severe service performance
• High temperature performance low temperature fluidity
• Excellent water separation which prevents corrosion
• Lower coefficient of friction
• Compatible with other oils

Royal Purple

• Case of 3 // 1 Quart Each
• Gear Lube
• Max-Gear Synthetic Gear Lube Oil 75W140

Royal Purple

• Made in United States
• Package height :8.89 cm
• Package length :28.956 cm
• Package width :8.89 cm

Mobil 1

Ford

• Super-slick long lasting lubricant
• Safely blends with other gear oils, petroleum, or synthetic
• Insures less gear noise and longer bearing life
• Stands up to high temperatures while maintaining lubricity
• Specifically designed for heavy duty and high performance applications

Lucas Oil

• For best performance, follow the manufacturer's recommendations in your vehicle owner’s manual.

Royal Purple

• Fit type: Vehicle Specific
• Package Dimensions: 30.48 H x 16.51 L x 16.51 W (centimetres)
• Country of Origin : China
• Package Weight: 3.447 kilograms

Lucas Oil

• Reduces noise and vibrations in the axle while providing protection under high loads, damage prevention to components, durability and performance that exceed conventional API GL-5 and MT-1 gear oils
• Synthetic durability for maximum protection under severe driving conditions and added assurance during extended drain intervals
• Superior high and low temperature performance. Exceptional stability at high temperatures extending the life of lubricant and axle. Improved thermal stability and unsurpassed shear stability for superior wear protection
• Friction modified for use in both conventional and limited slip axles
• Exceeds the service fill requirements of conventional and synthetic API GL-5 gear oils

Castrol