Rear Differential Fluid Inspection and Replacement: Inspection

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

Park the vehicle on level ground, and turn the ignition switch to LOCK (0).
Use solvent and a brush to wash any oil and dirt off the differential fluid filler plugs, any dry them with compressed air.
Remove the filler plug (A) and the sealing washer (B), then check the condition of the fluid, if the fluid is dirty or burnt, replace it.

Fig 1: Identifying Filler Plug And Sealing Washer
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Make sure the fluid is at the proper level (C). If the level is below the proper level, check for fluid leaks at the differential. If a problem is found, fix it before filling the differential with fluid.
The fluid level must reach up the bottom of the filler plug hole. If necessary, add the recommended fluid until it runs out, then reinstall the filler plug with a new sealing washer.