Red Line 75W140 Synthetic Gear Oil (1 Qt.)

Red Line's 75W140 is a full synthetic GL-5 gear oil formulated for hypoid and limited slip differentials in trucks, performance cars, and off-road vehicles. It arrives with enough limited slip friction modifier already blended in for most LSD applications, so you typically do not need to add a separate friction modifier additive.

The numbers tell the story on this oil. Viscosity runs 27.7 cSt at 100 degrees Celsius and 182 cSt at 40 degrees, giving it a viscosity index of 191, which means it stays stable across a wide temperature range. The pour point sits at minus 49 degrees Fahrenheit, so it flows in cold weather instead of turning into sludge. Red Line rates it to exceed API GL-5 specifications and meet BMW SAF-XJ standards.

Popular in Ford Mustangs, F-150s, Dodge Rams, Toyota Tundras, and Jeep Cherokees, this oil is a common choice for differential service on vehicles that see towing, hauling, or spirited driving. Sold in a 1-quart bottle, so order enough for your differential capacity.