![Amazon.com: Red Line (50305) Manual Transmission (MT) 90W Gear Oil - Synthetic Gear Lube - 1 Gallon : Automotive Amazon.com: Red Line (50305) Manual Transmission (MT) 90W Gear Oil - Synthetic Gear Lube - 1 Gallon : Automotive](https://m.media-amazon.com/images/I/71oe7Mrgl5L._AC_UF894,1000_QL80_.jpg)
Amazon.com: Red Line (50305) Manual Transmission (MT) 90W Gear Oil - Synthetic Gear Lube - 1 Gallon : Automotive
![Is this gear oil safe for my NA? Says it has friction modifier and can be used for both GL5 and GL4 applications. : r/Miata Is this gear oil safe for my NA? Says it has friction modifier and can be used for both GL5 and GL4 applications. : r/Miata](https://external-preview.redd.it/Ktx68wBlXU0JzPahNl8kHYcZwv53PTy31HzdoC7qEzo.jpg?width=640&crop=smart&auto=webp&s=0edb551f2091ff702d409d748f7cdcac34acedc5)
Is this gear oil safe for my NA? Says it has friction modifier and can be used for both GL5 and GL4 applications. : r/Miata
![Red Line MTL 75W80 GL-4 Manual Transmission Gear Oil 1 Qt(0.946ml) Honda/BMW/Ford (Redline), Zhapalang E-autoparts Red Line MTL 75W80 GL-4 Manual Transmission Gear Oil 1 Qt(0.946ml) Honda/BMW/Ford (Redline), Zhapalang E-autoparts](http://img.zhapalang.com.my/Service-Maintenance/redline-mtl-001.jpg)
Red Line MTL 75W80 GL-4 Manual Transmission Gear Oil 1 Qt(0.946ml) Honda/BMW/Ford (Redline), Zhapalang E-autoparts
![Oil for worm-gear drive - Stearns-Knight, Stutz - Our Cars & Restoration Projects - Antique Automobile Club of America - Discussion Forums Oil for worm-gear drive - Stearns-Knight, Stutz - Our Cars & Restoration Projects - Antique Automobile Club of America - Discussion Forums](https://content.invisioncic.com/r277599/monthly_2019_03/BB6C2261-9EC3-430D-B741-533E00014E73.jpeg.79163bf967b9e61384a2458615b07237.jpeg)
Oil for worm-gear drive - Stearns-Knight, Stutz - Our Cars & Restoration Projects - Antique Automobile Club of America - Discussion Forums
![Red Line (50304) MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant - 1 Quart : Amazon.ca: Automotive Red Line (50304) MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant - 1 Quart : Amazon.ca: Automotive](https://m.media-amazon.com/images/I/61iZ6pnD7aL._AC_UF1000,1000_QL80_.jpg)