Every 38,000 km or every two years.
1. Before starting work, let the vehicle drive for a few kilometers to warm up the differential lubricant, then jack up the vehicle and securely support it on axle supports.
2. Place a drain pan, rags, newspapers and socket wrench under the vehicle. Since the lubricant will be hot, wear rubber gloves to prevent burns.
3. Remove the filler cap from the differential; this is the upper of the two plugs.
4. With a drain pan placed under the differential, loosen the drain plug; this is the lower of the two plugs.
5. Carefully unscrew the drain plug until it is removed from the casing.
6. Allow all liquid to drain into a drain pan, then replace the drain plug and tighten it securely.
7. Read the instructions in Section Checking the differential fluid level and fill the differential with lubricating fluid.
8. Install the filler plug and tighten it securely.
9. Lower the car to the ground. After driving the first few kilometers, check for leaks from the drain plug.