Do you hear a whining, howling, or humming noise on the front side of your Mercedes-Benz? Maybe you already need to change your front differential fluid. Learn how to do it by following the procedures below.
Changing Mercedes’s front differential fluid is relatively easy, and most DIYers can complete this job in less than two hours.
What you will need
- Mercedes Differential Hypoid Gear Oil
- Mercedes part# 001 989 33 03 12, MBZ Approval: 235.7
- Hypoid Gear Oil (Differential Oil) SAE 75W-85 or 85W-90 (1 Liter)
- Mercedes Hypoid Gear Oil SAE 75W-85 Differential Transfer Lubricant
- Always call your Mercedes-Benz to verify the approved differential fluid.
- Transfer Pump
- 8mm Allen wrench
- Car Ramps
- Jack Stands
- Drive your Mercedes-Benz up on car ramps. Set the parking brakes. Place wheel chocks behind the rear wheels to prevent the car from rolling back.
- Secure the vehicle with jack stands.
- Slide under the vehicle. Remove the front splash shield. It is held in place with several 8mm screws.
- Locate the drain and fill the plug. Note that some models only have a fill plug. The same plug is used for draining the oil. If your Mercedes differential only has one plug, use a transfer pump to suck the oil out of the front differential.
- Always remove the fill plug first. You must remove the fill plug first to ensure you can get it off. You don’t want to drain the fluid and realize you can’t get off the fill plug.
- Next, remove the drain plug and allow the oil to drain. Pay attention to the color of the oil. If the oil has a silver look, it may indicate that the front differential bearings are failing and will need to be replaced soon.
- Once all fluid has drained from the front differential of your Mercedes-Benz, it is time to reinstall the drain plug. Replace the plug or the washer if a new drain plug is available.
- Add Mercedes differential fluid until the differential is full and you see fluid starting to drip from the fill hole.
- Reinstall the fill hole plug. Re-insert the filler plug at a torque of 30 ft/lb. Make sure you install a new copper washer.
- Lower your Mercedes-Benz and take it for a spin.
The pictures in this guide are taken from a differential fitted on 2006-2011 R Class W251, ML-Class W164, and GL Class vehicles. While the front differential is slightly different in E, C, and S-Class models, these instructions can be used as a general guide for all owners of Mercedes-Benz with 4Matic.
We hope you found this guide, “Mercedes Front Differential Fluid Change,” helpful. Check these troubleshooting and repair guides for more help on your Mercedes-Benz vehicle.