Engine oil and filter change on the B-Class 180CDI W245

This is the most modern car which I have written an oil change procedure about. What is the difference here compared to the older cars? To be honest not much! The only difference is the car computer needs to be told that an oil change has happened and the service interval be reset through an OBD2 diagnostics unit. The OBD2 diagnostics unit can be found quite cheap online, but make sure you get one that works for this model with the capability to reset service intervals and fault codes. Since the more basic ones can only read fault codes.

Preparation

Get the necessary parts and oil. Here you need a filter kit, which contains the oil filter element, two rubber gaskets for the filter housing and a new drain plug with a new copper washer. Make sure to not get the cheapest filter you can find, since in my experience the filter element can start to deteriorate if you have long service intervals. This car is rated at 15.000km between oil changes, but I suggest doing them at 10.000km.

Parts:

  • Oil filter kit
  • Oil: Keep at least 6L on hand- The car needs around 5,4-5,8L

Tools:

  • Jack and jack stands
  • Sockets
  • Oil drain pan

I tend to use Castrol’s oil picker to find which oil I need for any car, but if you prefer other brands then I have no objection. Anyway Castrol recommends Edge 0W-30, but this could change if you plan to use the car in more extreme weather conditions. Refer to the owners manual if in doubt.

New engine oil for 180CDI
0W-30 Oil for 180CDI

Procedure

The engine should be at operating temperature to make the draining more effective. So prepare the oil change after a trip, either back from work or after the store.

I’m always a bit shocked when checking the oil on diesels since it’s usually pure black in color after a relatively short time. This car had some time since the last oil change and the level was quite low. This did worry me a bit since the car is at 250.000km already. It is always a good idea to check the bottom of the oil drip pan for sludge and metal shavings to assess the condition of the engine every time when changing the oil. So with that in mind, hoist up the front of the car on jack stands. This car has a very low ground clearance and it’s impossible to access anything under there.

Start with locating the oil filter element in the engine bay. It is on the right side of the car just behind the turbo. It is a bit cumbersome to reach with a socket, but you don’t need any special filter tool to remove it. The access will be much easier if you have a socket with a joint as shown in the picture below. Take out the old oil filter and then move to beneath the car.

Oil filter 180cdi
Oil filter location. Use a socket with a joint to get better access behind the turbo

If you haven’t seen under this car, everything is hidden beneath plastic panels. You have to take at least 2 of the panels off to get access to the oil drain plug. The oil drain plug is also a joker to find, since it’s not where you expect it to be traditionally. It’s at the very rear of the engine far behind the front wheels. It is the most left plug on the engine block (see image).

Oil drain plug location B180CDI
Oil drain plug location on the 180CDI. You need to remove some plastic panels to find it.

I’m not sure what the plastic panels are for except aesthetics and hiding the under body. Also it can trap moisture and rust. They have some very subtle sound dampening effects and can keep some of the dirt away. Maybe it decreases air drag at high speeds? But I didn’t bother to put them back on. They were quite cracked and had a large hole due to the low ground clearance. I prefer seeing whats going underneath the car and the ability to wash off the salt underneath there especially in the winter.

Now that the drain plug is located. Start drain the oil and try not to loose the plug into the pan when opening it. The oil should drain a while until the dripping stops. Then take the new drain plug with the new copper washer and use that to plug the drain. Do not overtighten! Maximum 30Nm.

Draining oil from 180CDI
Draining oil from the 180CDI

After the drain plug is secured. Then it’s time to change the oil filter. The oil filter cap contains two rubber seals, remember to change both of them! Use a rag to clean up inside the oil filter housing for old oil. Mount the new filter onto the oil filter cap and then reinsert the filter cap into the filter housing. Tighten the filter housing to max 25NM. Over tightening will ruin the plastic so be careful.

Oil filter kit parts B180CDI
Oil filter kit parts. Note the two rubber seals, along with new drain plug and washer. See the old filter how deteriorated it is, it’s almost falling apart. Indicating cheap filter and overdue service interval. The new filter is a honeycomb structure and not a cheap paper filter like the old one.

Recheck that you actually secured the oil drain plug under the engine before you start pouring in the new oil. The car needs 5,4L to 5,8L, but there is probably some residue and the actual amount might be a little less. Start by pouring 4,5L. Level the car in order to make a proper reading of the dip stick. Then pour little by little until max level on the dip stick is achieved.

Oil pan with old oil from diesel engine
Inspect oil from the oil pan. Since this is a diesel it’s completely black. This is normal for a diesel. Also use your smell, does it smell really burnt? This could indicate overdue interval. Also check for sludge at the bottom of the pan which can indicate old oil. Check for metal shavings which can indicate bearing wear and poorly maintained engine.

Check the oil drain pan for assessing the health of the engine and if the service interval have been overdue. Luckily there were no sludge or metal shavings from my oil, but it smelt strongly burnt. Which with the low oil level may indicate an overdue oil service interval. Thankfully I switched this oil in this before doing any driving at all after getting it. The engine is quite strong and starts easy without any smoking indicating a healthy engine still. Phew!

Now the last part is to tell the engine computer that an oil change have been done and reset the service interval. The annoying wrench and reminder every time you start the car will then go away. Unfortunately I didn’t take pictures of this process, but it’s really a straight forwards procedure.

  1. Connect the OBD2 to the connector underneath the steering wheel.
  2. Select the car and engine type with manufacturing year
  3. Go on the menu which you can reset oil service interval. These can be different depending on the type of reader, but should be pretty obvious
  4. Set that oil service have been done, this will remove warnings on the dashboard
  5. While you’re at it, do a scan of error codes if any

Now you can do an oil measurement while the key is inserted and the engine is off. You can access this through the interactive computer in the dashboard through the buttons on the steering wheel. The car will then tell you if the level is OK or not.

If everything is OK and no service interval warnings. It’s time to start the engine. While the engine is running. Inspect underneath and see that there are no oil leaks form the drain plug and also check the oil filter housing for leaks. If no leaks, go for a small 5min drive. When back, recheck the dip stick level when engine is off. Refill more oil if necessary. Also recheck for leaks underneath and at the oil filter housing.

Robs out!

Author: Robs

Passionate about vintage Mercedes Benz where driving, maintaining and learning new things and teaching others on the black arts of car maintenance.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.