Brake Fluid Change for W211 by BrainS

5 minute read

Brake Fluid Change for W211

Compliments of BrianS @ http://mbworld.org

I decided it was about time to flush the system and figured another DIY might be helpful. The entire procedure took about 2.5 liters of fluid.

Here's the main supplies I used...STAR, Motive bleeder, and Pentosin Super Dot 4 which is the MB spec and OE part from what I can find, http://www.crpindustries.com/pentosi...uperDOT4_3.pdf , but much less at NAPA ($13 per liter) than going to the dealer for the same thing in an MB bottle. You'll also need an 8mm wrench for the rear bleeders and a 10mm for the front caliper bleeders. 

First I sucked out as much of the old brake as I could from the reservoir using a 60cc syringe I got from the farm store with a silicone hose suck on the end.

Hook up the bleeder.

Pump up the pressure to about 2bar.

Go to the SBC control unit screen and select General Servicing.

Then replace Brake Fluid...

Again..

Next screen reminds you of the bleed sequence...

At this screen make sure your bleed hose is connected and sitting in your container so when you hit F3 you can go crack the bleeder open while the SBC builds pressure. You'll hear some valves open and close and then a burst of fluid go into the drain container. After that it slows to a steady flow and the STAR screen will basically tell you what to do next.

Here's a sample screen after I finished with the left rear caliper and moved on to the front calipers. Each of the front calipers have two bleeders - one on the outside and one on the inside. Outside one's are bled first.

Almost done...moving on to last bleeder.

There will be a couple other screens after this which are self-explanatory. After those I removed the pressure bleeder and made sure the proper amount of brake fluid was in there and closed the sytem. The last thing I did was run this pressure check where there SBC tests the system to make sure it's holding the correct amount. 90bar was factory spec if I recall and mine was 88bar so I'm good to go. 

Install the plastic cover over the reservoir, shut off the ignition, start the car, check for any codes, and you're done.

I'll be flushing the coolant and changing the oil tomorrow.