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Demon Tweeks£112.55Visit shop Red Line 75W90NS GL-5 Gear Oil - 1 Gallon (3.7 Litres)
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The Red Line 75W90NS is a fully synthetic GL-5 gear oil designed for manual transmissions, transaxles, and differentials, particularly in competition settings. Its primary benefit is providing maximum component protection and facilitating easier gear shifts across a wide temperature range, especially under extreme conditions. A key consideration is that it lacks friction modifiers, which is ideal for plate-type limited-slip differentials (LSDs) to ensure maximum lock-up, but it may cause noise in road cars unless a friction modifier additive is used.
| Model Part Number | 58305 |
|---|---|
| Brand | Red Line |
It is suitable for the drivetrain components, but if your road car has a clutch-type limited-slip differential (LSD), you may experience noise or chatter. For quieter operation, consider adding a Red Line friction modifier additive.
The 'NS' in 75W90NS stands for 'No Spool' or 'No Slip', indicating it lacks the friction modifiers found in some other Red Line gear oils. This is intentional to provide maximum lock-up for clutch-type LSDs in competition. Other oils may contain friction modifiers for smoother, quieter operation in road applications.
Start with a small amount, such as 2-4 ounces per quart of gear oil, and test. Add more gradually if needed, but avoid over-adding as it can reduce LSD performance. Consult Red Line's technical recommendations for specific guidance.
It is generally recommended not to mix different types or brands of gear oils, especially synthetic with conventional, as it can compromise performance and protective properties. For best results, drain and refill with Red Line 75W90NS.
Red Line Synthetic Oil typically warrants its products against defects in materials and workmanship. Specific warranty terms may vary; it's best to check the official Red Line Synthetic Oil website or product packaging for the most current information.
Yes, Red Line 75W90NS is formulated to meet and exceed API GL-5 specifications, as well as API MT-1 and other industry standards.
Ensure the correct viscosity is used for the ambient temperature and application. For very cold climates, the 75W90NS formulation is designed for easier cold shifting. If the issue persists, check for internal transmission wear or damage.
This oil does not contain friction modifiers, which can cause noise in standard road car clutch-type LSDs. Add a compatible friction modifier additive to the oil to quiet operation. Ensure the oil level is correct.
Inspect and replace any worn or damaged seals, gaskets, or O-rings. Ensure drain and fill plugs are securely tightened with appropriate sealing washers if required.
Verify that the oil is compatible with your specific LSD type. For clutch-type LSDs, ensure no friction modifiers were added if maximum lock-up is desired. If issues persist, the LSD clutch plates may be worn and require servicing.
Compatibility:
This gear oil is API GL-5 and MT-1 compliant and meets or exceeds numerous manufacturer specifications including MIL-L-210SE, SAE J2360, and recommendations from Alfa Romeo, Ferrari, GM, Porsche, and Subaru. It is suitable for use in manual transmissions, transaxles, and differentials, particularly those used in competition. It is compatible with clutch plate type Limited Slip Differentials (LSDs). For road car use with an LSD where noise is a concern, a friction modifier additive may be required.
Setup:
Ensure the vehicle's differential or transmission is drained completely of old fluid. Clean any debris from the drain and fill plugs. Fill the component to the manufacturer's recommended level, typically until the fluid reaches the bottom of the fill plug hole. For manual transmissions, consult your vehicle's service manual for the correct fill procedure and capacity.
Care:
Regularly check for leaks around seals and drain/fill plugs. Monitor the fluid condition during routine maintenance; excessively dark or burnt fluid may indicate a problem requiring further inspection. While this is a high-performance synthetic, changing the fluid at recommended intervals or based on usage (e.g., after intense track days) will ensure optimal protection and performance.
