How To: Mercedes-Benz Rear Differential Fluid Drain & Fill

    This guide was written for the Mercedes-Benz W123 Cars but is applicable to many other models. If you have any questions feel free to text me anytime. Thanks! (928)219-2563
  • Servicing your rear differential is recommended every 30,000-60,000 miles

Tools and Parts Needed: 

  • 14mm Allen Socket
  • Fluid Pump
  • Jack w/ 4 Jack Stands
  • Differential Fluid
  • Differential Plugs(Optional Can be reused)

Step 1. Take the car for a short drive to warm up the fluid

Step 2. Jack up the car and put stands in the front and rear. The car must be level.

Step 3. Always remove the upper fill plug first. Then remove the lower plug and drain the fluid. Use a 14mm Allen

Step 4. Reinstall the drain plug and fill with fluid using a pump. Fill the rear differential until fluid starts leaking out. Reinstall the fill plug