Red Line MT-90 75W90 GL-4 Full Synthetic Gear Oil – 1 Quart

Upgrade your manual transmission with Red Line MT-90 — the industry standard for smooth, reliable shifting in performance vehicles. A full-synthetic, ester-based lubricant, MT-90 provides the perfect balance of gear protection and synchronized coefficient of friction, ensuring precise and quick shifts in all conditions, including cold starts.

Key Features

• Brass Synchro Safe: Formulated without the reactive sulfurs found in GL-5 oils that damage sensitive brass synchronizers — ideal for Nissan (SR20, KA24, RB), Mazda, Mitsubishi, and Toyota manual transmissions
• Eliminates Notchy Shifting: Shear-stable formula maintains consistent viscosity across temperature ranges, drastically reducing or eliminating the notchiness experienced when shifting cold
• Optimal GL-4 Viscosity: 75W90 grade satisfies GL-4 requirements with a viscosity similar to 5W40/10W40 engine oil — broad compatibility across JDM and European platforms
• High-Performance Protection: Superior gear protection, longer synchronizer life, and excellent thermal stability for street, autocross, and track use
• Full Synthetic Ester Base: Outstanding thermal stability and shear resistance for consistent protection over extended service intervals

Specifications

• Part Number: 50304
• Viscosity: 75W90
• Standard: API GL-4
• Base: Full Synthetic Ester
• Volume: 1 Quart (946mL)
• Application: Manual transmissions requiring GL-4 75W90

Note: GL-4 rated — not a GL-5 fluid. Always verify your transmission’s fluid specification before ordering. Safe for brass synchronizers.