Oils, Fluids and Sealer› Oils, Fluids and Additives

Red Line

75W90 GL-5 Gear Oil

$25.99

SKU: 50204 / 57904

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return

Overview

The Red Line gear oil line includes 75W90 GL-5 and MTL 75W80 GL-4 formulas designed for specific drivetrain applications. The 75W90 GL-5 is a full-synthetic, ester-based lubricant for hypoid gears and limited-slip differentials. The MTL 75W80 GL-4 is formulated for manual transmissions and transaxles, providing balanced friction for synchronizers.
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The Red Line 75W90 GL-5 and MTL 75W80 GL-4 are full-synthetic, ester-based gear lubricants engineered for distinct automotive drivetrain needs. The 75W90 GL-5 formula contains extreme-pressure additives and friction modifiers designed specifically for hypoid gears and limited-slip differentials to reduce sliding friction and lower operating temperatures. In contrast, the MTL 75W80 GL-4 is optimized for manual transmissions and transaxles, featuring a coefficient of friction specifically balanced to ensure proper synchronizer engagement and prevent notchy shifting, especially in cold climates. Compatibility and application are critical due to the chemical differences between these formulations. The 75W90 GL-5 is not for use in most manual transmissions with synchronizers, as its high slipperiness may cause gear clash. Conversely, the MTL 75W80 GL-4, as well as MT-LV, MT-85, and MT-90, are not for use in differentials with hypoid gears. Users should strictly adhere to these exclusions to ensure proper component life and performance, as using the wrong oil can cause mechanical damage or poor shift quality. Both formulas offer superior shear stability, reduced oxidation, and consistent film thickness across a wide range of temperatures compared to conventional alternatives.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandRed Line
Part Number50204 / 57904
CategoryOils, Fluids and Sealer
5,000+ Trusted brands
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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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