Mercedes-Benz C-Class: How to Change Oil

As far as routine maintenance goes, engine oil is the number one item that is maintained the most. This is for good reason, as it keeps the entire engine lubricated while it is turning in circles thousands of times a minute. Learn how to change the oil on your C-Class here.

By Weston Chadwick - May 19, 2015

This article applies to the Mercedes-Benz C-Class (2007-2014).

Engine oil is pumped up from the oil pan at the bottom of the engine and makes its way though the engine by machined passages. As the oil wears, it loses its ability to eliminate friction between metal components. This creates heat which causes engine wear. It's important to have your oil at the correct level. Too little oil will keep the required pressure from being reached, while too much will cause air bubbles to form which reduces the efficiency of the system. Keep reading to learn how to replace the oil in your C-Class.

Materials Needed

  • 27mm socket
  • 13mm socket
  • 8mm socket
  • 3/8" ratchet
  • Fluid extractor (optional)
  • Small flat head screwdriver
  • Oil catch pan
  • Rags
  • Approved oil and filter

The c250 has a turbo four cylinder engine. The c300 and c350 have a v6 engine. Both will be covered here.

Step 1 – Remove the engine cover

The engine cover can be removed by grabbing the sides and the front/back. Then pull up and away from the engine to pop the cover off the mounts it sits on. The V6 engine cover is two piece, and you will only need to remove the front section.

Figure 1. Removing the front portion of the cover on the c300 and c350.

Step 2 – Remove the oil filter

For the turbo four cylinder, locate the oil filter housing behind the engine. Remove the cap with a 27mm socket. As you begin to lift the oil filter out of the housing, place a rag beneath the filter to keep oil from dripping onto the engine.

  • Figure 2. The cap on the oil filter housing says 'turbo' in yellow.
  • Figure 3. The oil filter housing cap has been removed.

The V6's oil filter housing is at the front of the engine.

Figure 4. The red arrows indicate the location of the filter cap and oil filter housing on the V6.

Step 3a – Begin fluid extraction (optional)

If you are using a fluid extractor, then this step is for you. If you are not, skip to Step 3b.

Hook up the hoses of the extractor for the right direction of flow. 'In' should be connected to the oil dipstick tube, while 'out' should be in a container.

Move on to Step 4 once finished.

Figure 5. A fluid extractor.

Step 3b – Remove the lower splash shields

If you choose to not use an oil extractor, you will need to remove the lower splash shields. They are held on by 8mm fasteners.

Figure 6. Items 60 and 100 show the front and rear lower splash shields.

Step 4 – Replace the o-rings/filter on the oil filter cap

The c300 and c250 both have three o-rings. Use your screwdriver and pry them off the cap.

  • Figure 7. These are the three o-rings on the c250.
  • Figure 8. The three o-rings on the c300 oil filter cap.

Slide the oil filter back onto the cap. Give it a firm push against the cap to ensure it's seated correctly. Screw and tighten the cap back onto the filter housing.

Step 5 – Drain the oil

The drain bolt on the c250 is 13mm and located on the driver's side of the oil pan. On the c300 and c350, it is also on the driver's side directly in front of the transmission.

  • Figure 9. The oil drain bolt on the c250.
  • Figure 10. The drain plug location on the V6 engines.

Re-install the drain bolt when the oil leaving the pan slows down to a drip.

Let the oil drain for approximately 15 minutes, then reinstall the drain bolt to about 20 ft./lb. of torque. If you don't have a torque wrench, this can be best equated to snug, not brutally tight; you can damage the oil pan by over-torquing the drain plug.

Step 6 – Fill the engine with oil

You will need 8.5 qts. of oil for the c300 and c350. The c250 will need 5.8 qts.

Once the engine oil is filled, start the vehicle and let it idle for 30 seconds. Turn the engine off and check for the correct oil level on the dipstick.

Step 7 – Reset the oil indicator light

Follow the procedure, as shown in Figure 11.

Figure 11. The procedure to reset the service light.

You have now completed the oil change on your Mercedes-Benz C-Class.

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