Which of the following actions is advisable when dealing with a differential during maintenance?

Following OEM (Original Equipment Manufacturer) recommendations for gear lube specifications is critical when performing maintenance on a differential. The manufacturer’s specifications are the result of extensive testing and are designed to ensure optimal performance, reliability, and longevity of the differential. Gear lube plays a vital role in reducing friction and wear, dissipating heat, and providing lubrication for the moving parts within the differential. By using the recommended specifications, you ensure the fluid has the appropriate viscosity, additives, and performance characteristics required for the specific design of the differential.

Using the wrong type of gear lube can lead to inadequate lubrication, increased wear, and potential overheating, which may compromise the differential's operation. Following OEM guidelines also helps maintain any warranty on the vehicle and ensures compliance with service standards that manufacturers expect from maintenance practices.

Other practices such as mixing old and new gear lube could lead to contamination and degradation of the lubricant's properties, while using used components to replace the differential may result in reliability issues and poor performance. Ignoring signs of leakage could lead to a complete failure of the differential system over time due to lubricant loss, leading to significant repair costs. Therefore, adhering to the OEM recommendations is essential for maintaining the integrity of the differential.