Home > DIY > C-Class > DIY Rear Differential Oil Change Mercedes-Benz
YouTube video

DIY Rear Differential Oil Change Mercedes-Benz

DIY How To Change Differential Oil, Problems and Symptom

This DIY guide will show you how to replace the rear differential fluid on a Mercedes-Benz. Changing the differential fluid will help avoid costly differential repairs down the road. Some symptoms of a bad differential on a Mercedes-Benz are whine, rumbling, humming, growling, noise while turning, vibration, loud clanks, or grinding at low speeds. These symptoms can be noticed under stress, at high speed, or when taking a corner.

A lack of differential fluid can cause these problems. We recommend replacing the rear differential oil on your Mercedes-Benz every 30,000 to 50,000 miles.

You replace the differential fluid costs under $50 if you purchase oil and tools online. Links are provided below. This is an easy task that you can tackle yourself. It’s not any more difficult than replacing the engine oil. To complete this job, you must have the correct oil screw wrench and oil transfer pump.

By following these instructions,  you agree to have read and agreed to our Terms and Conditions.

Required Parts & Tools

Here is a list of the parts and tools needed to perform the rear differential fluid change on a Mercedes-Benz.

DIY Instructions. How to change Mercedes-Benz differential fluid

Safely jack up your Mercedes-Benz.

Place the jack at the rear, driver-side jack support. Do not use the jack to keep the vehicle off the ground. Always use jack stands.

Locate Rear Differential

Locate the rear differential at the rear of the vehicle.

Oil Drain Screw

Locate the oil drain screw at the bottom of the rear axle assembly. Remove the screw. Use the Mercedes-Benz Fluid Drain Wrench Tool listed under the parts section above to remove the screw.

Drain Oil

Drain the differential oil. If the car was in use right before you started to change the differential oil, be careful, as the fluid may be hot.

Oil Filler Screw

Locate the oil filler screw. It should be above the oil drain screw you removed in the previous step. Remove this screw. Wait for the differential fluid to completely drain via the bottom oil drain screw and install the oil drain screw back on.

Mercedes Hypoid Gear Oil SAE 75W-85 (1L) differential transfer case lubricant

You will need approximately 1 liter of differential transfer case oil SAE 75W-85. To check the exact capacity of your car, look it up in the owner’s manual specifications section. In this case, we used the Mercedes part# 001 989 33 03 12, MBZ Approval: 235.7 MBZ_001989330312948622 001 989 33 03 12, 001 989 3303, 0019893303

Fill Differential

Use an oil pump such as the Plews Lubrimatic Fluid Quart Pump to transfer the new oil into the rear differential via the oil fill screw. You will know when the differential is full when the oil starts to spill via the oil fill screw. To get the level correctly, you should ensure the car is leveled.

Video: How To Change The Differential Fluid On Your Mercedes Benz

YouTube video

Common Mercedes-Benz Differential Problems

Problem Cause
Whirring noise when decelerating. Bad pinion bearing.
Loose pinion bearing preload.
Whine or how during acceleration. Worn ring or pinion gears.
It was rumbling when driving at over 20 mph speeds. Worn carrier bearings.
Clunking at low speeds. Possible broken ring or pinion gears.
Clunking during cornering and turning. Possible low on oil. Worn clutches. They have broken spider gears.

More How To DIY Differential Oil Change Guides

Here is a list of other guides on how to replace the differential oil fluid on a Mercedes-Benz. These are links to external sites not owned by MercedesMedic.com.


Mercedes-Benz Gear Oil Specifications

Mercedes-Benz gear oil specifications and requirements. 

The gear oils are approved for MB vehicles.

Hypoid gear oils sheet 235.0/.6/.7/.8/.9/.15/.16/.17/.20/.31/.61/.62

Applicable Models



Did you find this guide helpful? Use the comments section below to give us feedback. Tell us what we can do to improve this article.


  1. Remove Oil Filler Plug FIRST then the Drain Plug….. this will allow external air pressure within the axle casing, assisting the oil to drain at a greater rate….and pick up any debris on its way out. It will also confirm, or not, whether there was sufficient oil in the axle before you refill.
    Just like when doing an engine oil change….the oil filler cap should be removed prior to removing the sump drain plug.

  2. With each and every thing I do to my wife’s MB, Chevrolet and Ford just keep looking better and better and better!

  3. Never open the drain plug before you know the fill plug will come off!
    Not fun to find out you can’t refill the differential AFTER all the oil has been drained!

  4. Is the bolt/plug tool needed, is it the same for the front?

Leave a Reply

Your email address will not be published.

All rights reserved Notice: CLOUD