Hey everyone,
I'd appreciate if someone could provide some help on changing the brake and ABS fluid for a ML320 (2000). A step by step direction will be much appreciated (including filling and bleeding). By the way, does ABS and brake share the same fluid?
Thanks in advance,
BR/PY

I appologize if this seems rude, but if you are asking questions like this you should NOT be working on your own brakes, as they are the most critical safety feature of your vehicle. I would let a pro handle this for you for now, but learning is always a good thing.

Yes, it is all the same fluid, as it is one system, not two. Bleeding can be done many ways: with an automatic pressure bleeder, with a vacuum bleeder, or (my personal favorite) the slow old-fashioned way. The old fashioned way involves sucking out most of the fluid from the master cylinder and refilling it with new fluid. Then, working from the wheel farthest from the master cylinder to the one closest, one person breaks open the bleed screw (once a drain tube is on it) while another pushes the brake pedal to the floor. Then you close the screw, let the pedal up, and then do the process over again until the old fluid is cleared from that caliper/line. You then move on to the next one. You need to refill the master cylinder from time to time with new fluid as you go. Time consuming and messy, but still the best way to do it if you want a 100% air free system.

Keep reading and learning about how it all works, but again, I would not attempt this on your own until you not only fully understand how the brake system works, but also how to do the work.

I can just see the indies rubbing their hands together as you tell our readers to pump the brakes to the floor. BAAAAAD! More master cylinders are killed this way than by normal attrition.

Why? Normal brake usage creates a swept area in the two master cylinders that is essentially clean and smooth. Corosion and debris accumulate in the area not normally swept by using the brakes. As soon as you push the pedal into the unused zone, you run the risk of tearing the seal cups and damaging the master cylinder

The best way to bleed mercedes brakes, especially with ABS/ETS etc, is the pressure bleeder. You can buy one for less than $50 with a cap that fits a lot of MB, BMW, etc. It is easily a one man job and no contaminents enter the system, just clean brake fluid.

If you must bleed by pumping the brakes, cut a block of wood to stop the pedal at the same point as it normally goes to. Do NOt push the pedal to the floor!

Jim in Phoenix

I disagree. The whole point is TO run the master cylinder through the full range of motion, and to push any crud out--that is part of the reason you bleed the brakes. Since you should regularly change your brake fluid, it should never get so bad in there that you would tear out any seals. I find the fact that it exercises the full range of travel to be a + not a -.

As for pressure bleeders, I am still uncertain about them. I HATE Vac. bleeders, as I can never get a good air free bleed with them. However, my expereince with pressure bleeders is much more limited, but I know of more than one person who has cracked a master cylinder Res. trying to crank the pressure cap down super tight to avoid leaks. I know you do not need to do that, but people do it anyway.

I have bled everything from my MB to my race car to my antique truck using the "pump" method, and never had a problem. Maybe it's just me...I am a stick with what has worked for me type.

Thanks both of your inputs. It's great to get such good advice from nice folks like you. I appreciate your safety concerns and I will take your suggestion with caution and careful considerations.
Thanks again,
BR/PY