Few drivers realise that limited-slip differentials depend as much on oil chemistry as on hardware. Friction modifiers in LS gear oils tune how smoothly clutch packs engage, shaping turn-in stability and traction over ruts and jump landings. In rally use, sudden load spikes and temperature swings can shear the film and invite chatter; a stable base oil and balanced additives help maintain a predictable lock without harshness. For mixed gravel and asphalt and frequent tight exits, an LS-rated gear oil of suitable grade, such as 75w140 LS GL-5, supports consistent torque transfer.