Does the Rear Differential Need Replacement?
1 Answers
Rear differential fluid needs to be replaced, with a typical replacement interval of 80,000 to 100,000 kilometers. Changing the differential fluid prevents excessive wear on the vehicle's differential gears, which could lead to differential damage. Differential fluid is the lubricant for the rear axle gear transmission mechanism, also known as gear oil. Its primary functions are lubrication and cooling. Due to variations in the positional relationship of gear axes and tooth profiles, there are significant differences in contact stress and relative sliding speed at the meshing surfaces of gears, necessitating the use of different gear oils. Failure to replace differential fluid increases friction between gears in the differential structure, raising vehicle fuel consumption and potentially damaging the differential, differential lock, and other components over time. The functions of differential fluid include forming an oil film on gear meshing surfaces to reduce friction and extend component lifespan, as well as dissipating heat generated by friction pairs through fluid circulation for cooling purposes. Its working principle involves maintaining high temperatures in the differential lubricant during high-speed driving—far exceeding engine oil temperatures—to ensure proper vehicle operation.