How to change Diesel Engine Oil on a Mercedes-Benz OM651 2.1L Easy DIY
Is it time to change the engine oil in your Mercedes-Benz OM651 2.1L Diesel Engine? Learn how to replace your Mercedes-Benz engine oil and filter by following the steps below. The video and pictures are from a 2014 GLK250 BlueTec, but the procedure applies to other Mercedes-Benz models equipped with the OM651 engine.
Are you more of a visual learner? Follow along with our video guide below!
What you will need
There are a couple of tools and parts you will need to replace the engine oil in your Mercedes-Benz OM651 engine:
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Parts
- Engine Oil SAE 0W-40
- Capacity: 5.9 US qt (5.6 l)
- Specification: MB 229.5
- 1 quart (US) = 0.9463 liter
- Engine Oil Filter
- See the part numbers below.
Tools
- Oil Filter Wrench or Pliers
- Oil drain pan
- Funnel
- Work Gloves
- Ramps or Floor Jack
- Jack stands (x2)
- Ratchet
- Metric Sockets
- Wheel Chocks
- Torque Wrench
Procedure
1. Jack up the vehicle. Drive the vehicle up onto ramps, or use a floor jack, and place the transmission in Park.
Next, turn the ignition off and remove the key.
2. Secure the vehicle with jack stands. The jack stands must be used to support the vehicle frame. Do not place a jack stand under the engine or suspension components. Place the jacks under the designated jack points around the vehicle. If you’re not sure where they are, look up the location online, or find it in your Mercedes-Benz’s user manual.
3. Place wheel chocks behind the rear tires to prevent the vehicle from rolling; alternatively, use a block or large brick if wheel chocks are unavailable. Ensure parking brakes are engaged. 
If the engine has been running for a long time, allow it to cool down for at least 15 minutes. If the engine is already cool, you can continue to the next step.
4. Remove the splash shield from under the engine. To remove the splash shield, you need a ratchet and socket to remove the eight 8 mm bolts around it.
In some models, you have a combination of screws and plastic retainers. Please remove all of them to drop the cover and access the oil drain bolt. 
5. Slide a drain pan and place it under the drain plug. Make sure the drain pan is large enough to catch all of the engine oil.
NOTE: Slightly offset the drain pan because, when the drain plug is removed, oil will shoot out rather than down.
Use a 13mm wrench to remove the drain plug. 
Loosen the drain bolt by turning it counterclockwise. If removing the drain bolt is extremely difficult, check that you are not turning it in the wrong direction.
4. Drain engine oil.
⚠️CAUTION: If the engine is still hot, the engine oil will also be hot, which can cause burns if it comes into contact with your skin.
Carefully remove the drain plug and let the engine oil drain for several minutes.
5. Replace the copper washer. Replacing the copper washer every time you change the engine oil is recommended. Do not reinstall the drain plug without a new copper washer.
6. Install Drain Plug. Initially, screw it by hand to avoid cross-threading. Use a torque wrench to tighten the drain plug to specification; do not use a breaker bar. See the recommended torque at the end of this guide.
7. Locate the engine oil filter and replace it. Use an oil wrench to remove the filter cartridge and keep a drain pan nearby. Oil may drip when you remove the filter cartridge. Remove the old filter cartridge, then put the new one in. Replace the o-rings on the filter cartridge as well.
8. Put the engine filter back in place and use an oil wrench to seal it properly—torque to 25 Nm.
9. Open the engine oil cap and add engine oil. Clean the area around the cap with a damp paper towel or microfiber cloth to prevent dirt and debris from entering the reservoir.
Use a funnel to pour the engine oil and prevent spills.
10. Check engine oil level. If you had the engine running or just added oil to the engine, you should wait at least five minutes to take the subsequent measurement. This will allow the engine oil to return to the pan so that you can take an accurate measurement. If the level is low, add one quart at a time, wait a few minutes, and recheck the levels. 
11. Reset the oil service reminder on the instrument cluster.
12. Inspect the engine for oil leaks from the drain plug and filter.
Torque Specifications
- Oil filter: 25Nm
- Oil drain plug: 30 Nm or 23ft-lbs
One Newton meter is equal to 0.7376 ft-lbs, rounded to 4 decimal places. To convert newton meters to foot-pounds, multiply your figure by 0.7376.
Applicable Oil Filters
- Fram CH11277 replacement filters
- Beck/Arnley 041-0867
- CARQUEST 94026
- CHAMP P1013
- CHRYSLER 68091826AA
- CHRYSLER 68091827AA
- FIAT K68091826AA
- FIAT K68091827AA
- Fleetguard LF4000
- HASTINGS LF723
- HENGST E11HD204
- JURA SO7217
- KNECHT OX153-7D2ECO
- Land Rover LR022896
- LUBER-FINER P1013
- MAHLE OX153-7D2
- MAHLE OX153-7D2ECO
- MANN & HUMMEL HU7010z
- MANN & HUMMEL HU718-4Y
- MERCEDES-BENZ 1121840425
- MERCEDES-BENZ 6511080009
- MERCEDES-BENZ 6511800109
- MERCEDES-BENZ 6511800309
- MERCEDES-BENZ 6511840025
- NAPA 100026
- Nissan 15209-HG00A
- PUREPRO PL91013
- Purolator L21405
- ROVER LR022896
- SERVICE CHAMP WP1013
- STP S11277
- WARNER WP1013
- Wix WL10026
- Wix WL7470
We hope you find the Mercedes-Benz OM651 2.1L Diesel Engine Oil Change DIY guide helpful. Check these troubleshooting and repair guides for more help on your Mercedes-Benz.
