BenzVince

Tonight, I got the brake lining wear message on my car. That i realized the brake pad are worn. I'm going to tackle this job over the weekend to do the pads myself. Before I break out doing the task, is there any suggestion or advice that I need to know before doing the task, such as special tools? Sensor?

JimE430

Not exactly sure, but most pistons have to be rotated as you depress them. You can get this tool at most auto parts. Use the correct lube on the back of the pads or they will squeek (squeeking comes from oscillation of the pads against the piston, not the pad on the rotor) Also take the cap off the fluid resevior, and keep an eye on the level as you depress piston. If you have "topped off" your fluid, and most times dont need to, the fluid will overflow. In ALL cases you should have your rotors turned. If they are below specs, you need to replace. Rotors get hot, and then distorted. You will feel this after a new brake job if you do not turn the rotors. Hope this helps,
Jim

JimE430

Oh yeah, the sensor. Carefully remove it (wiggle) and it will be reused.

JLLG

The light gives you ample warning before the pad change is actually needed. For myself, I would feel comfortable driving another 1000 miles if I needed the time.

-Rotating pistons, never heard of that, does not make sense to me. The MB WIS does not mention this either.

-Brake Anti-Squeal paste is the name versus brake lube.

-Everything I have read states to NOT turn your rotors. If they are in spec and not warped, don't change. On average it seems that one rotor can sustain 2 pad changes.

-I would at least change the sensor that set off the light, it has to be worn a little. These sensors are not that expensive.

OceanView

Buy the parts online. Much cheaper.
Especially the sensor. It was only $1-$2 but the dealer charges $7.50 each.
You will need 2 of them.

Pretty easy to do. Also, as JLLG mentioned, dont turn the rotors.
They will wear down fast enough and require new ones soon.
I never turned them and they were fine.

MARK CUMMINS

Once the Brake Pad light is on the Sensors are No Longer Reuseable..
The Sensor wire is broken and that what turns the Brake wear light on

Do NOT Turn the Brake rotors..Most of the time they end up UNDERSIZE!
The Mercedes rotors go about Two sets of Pads to a rotor...

Try Mintex Pads..Decent Price...LESS DUST!

Also You Might want to flush the Brake system ..Very easy to do!
It Should be done Once a Year!

JimE430

JLLG, sorry I did not use the correct term, "Brake Anti-Squeal paste" (same difference) As I said, I was not sure about the rotating part. If you have never had to rotate a piston while depressing it you have not done many brake jobs. I know MBZ says not to turn the rotors, but why? Every rotor I have turned has been warped to one degree or another. Heat will do that. Yes, you can put your new flat pads on an uneven surface and yes they will work, however, they will not last as long. Also the reason you only get 2 brake jobs per rotor. Maybe at $70.00 a rotor you dont mind throwing them away, but if you get a really good set at $150.00-200.00 each, I bet you have them turned! Not trying to start any fights, just trying to offer some advice. I will be the first to admit I was wrong, but your response (JLLG) was pretty rude.

JimE430

MARK, you are correct, many rotors cannot be turned or they will be undersize, but if you dont let them (pads) go too long or cause too much damage, there is no reason not to have them turned. It will not hurt, and for a couple of bucks, it can help.

JLLG

JimE430,

Take it easy, I apologize if I offended you. I had written a longer more appropriately worded response but I hit the backspace button and lost the whole thing. I hastily rewrote the response with intentions of only helping Benzvice. The following are some comments that I hope you do not find offensive.

Why don't you take time to explain this rotating concept instead of getting upset about it? I just don’t understand how you can do this without marring the piston surface and comprising the seal. I purchased this tool and it works really well, http://www.samstagsales.com/mercedes/mb000589524300.jpg It is a little pricey but it is generic enough to use on most cars.

Regarding the Anti-Squeal paste, again I was only trying to help. If you ask for brake lube, the store may not now what you are talking about. Again, why take offense?

As for turning rotors, Oceanview agreed with me, why did you not flame him? In addition, turning rotors obviously removes material, therefore reducing the heat capacity. This reduced heat capacity will increase the chance of warping due to heat. OEM type rotors only have about 2.5 mm service range, this is not much to play with. I do agree that all rotors get warped to some degree but turning with every pad change seems like a waste of time and money. If I am not mistaken, more and more manufacturers are making the rotors a more “disposable” part. Non OEM parts are probably an exception to this in some cases.

JimE430

I apologize if it sounded like I was flaming you, I just had a bad day. A lot of the cars I have delt with were able to have the rotors turned. You are correct that nowadays a great deal of automakers are producing "throw away" rotors. Having not yet done my brakes I was not sure what kind of calipers it has. I have a brake tool similar to yours. On some domestic cars the piston has a cross machined on the face. You cannot simply push the piston in. The tool fits in the cross and you rotate the tool as you push the piston in. A real pain! Glad to hear my car will be easy. Again, sorry I wil be more considerate in the future.

Top Jimmy

Now that you two have sorted that out, lets have a group hug.

Actually, at the risk of beating running this into the ground, let add my two cents worth given that I just did this job last weekend on my '96. First let me say that I have done brakes on maybe 30 cars or so in the past -- some American, some imports but never a MB.

I did a lot of reading here and everywhere else to psyc myself up for this, after all this is not only a Benz... it is MY Benz The job was very easy and very much like every other front disk brake job I have done. I won't bore you with the play-by-play details, but only the "differences" about doing this job, or in some cases, the things I should have thought of before or during the process. (Old-timers at this please cut me some slack.)

I replaced the rotors with stock Balo’s with no cross-drilling or slots. I would have loved the look, but with stock wheels it really didn’t matter, and I do not need the additional performance. I got the Textar pads in the Yellow Box, with which I am happy. Limited dusting and seems to be diminishing now that I have about 300 miles on them. I bought new electronic sensors for something like $3.00 and the official MB Anti-Squeal Paste.

Now to the things I wished I knew, thought about, or remembered at the time.
1) Like for many cars now days, you need a Torx wrench or socket (No. 45, I believe) to take off the calipers.
2) Because MB uses bolts instead of studs there is an allen head bolt that hold the rotor on. You should take this out before you try to remove the rotor.
3) Smear the Anti-Squeal Paste on the back of the pads and allow enough time for it to partially dry before reinstalling – otherwise is just squeezes out the side and become less effective.

That is really all of the things that I learned or wished I had remembered. Of course you need to bleed them down afterward and, yes, as you push the piston back into the caliper, you should have the cap off of the brake fluid reservoir – there will likely be overflow without removing some first. (I don't know about the rotating issue of the piston. I am pretty sure that mine did not rotate when I pushed them back into the caliper.)

You can read lot of other good information about what MB recommends or says to avoid, like “don’t push the fluid back through the lines, but open the bleeder screw instead”, “flush the fluid entirely”, or “don’t turn the rotors”. You have to make up your own mind about these things. For me the procedure I did worked very well. I have no issues or regrets – oh, and no squeal either.

PM with any questions.

Good luck!

X72

I had a VW New Beetle. In order to replace the rear disc brake pads, a special tool is needed that pushes the piston in as it rotates it. If you were to push the piston straight in, it would ruin the parking brake mechanism. The rotation had to be in a specific direction (I don't remember if it is clockwise or counterclockwise). This may be true on Audi's as well.

I now have a 2003 E 320. Even though there are people who have changed the brake pads on their W211 E 500's, I have yet to see pictures posted for an E 320 so I do not want to experiment with the SBC braking system. So for you guys with W210's, a definite disadvantage of the W211 is that I am not at all confident to tackle replacing the disc brake pads myself which I would be happy to tackle on a W210.

William
2003 E 320

Gregs210

Folks, I just did this last weekend on my 2001 E320. In no particular order, here's some information. I've been trying to put together a comprehensive post, but the damnable limitations on pics (both size and number) has irritated me enough that I've put it on the back burner.

SENSORS: There is NO wire that breaks. You actually can reuse the sensor if you replace the pads soon enough. I drove about 1,500 miles after mine first came on and the first attached pic shows it chewed through well into it; I thought it was worth replacing since it was about half gone (and would thus limit the warning time in the future). The second pic depicts the insertion of the new sensor into the new pad. The wire connection back to the car is a simple plug-in, just make sure you use even pressure on both sides of the connector. The sensor itself consists of a plastic-insulated piece of metal that actually inserts into a hole in the pad near the backing plate. As the pad wears the plastic is uncovered and then eroded; when the metal is exposed it touches the rotor, thus closing the circuit and triggering the wear indicator. I got mine from parts.mbz.org for about $1.50 each.

ROTORS: MBZ specifies that if the rotors are worn/warped/damaged, they should be replaced, not turned. If you are NOT replacing them, do rough them up with some emery cloth, gentle swirling motions to clean off some of the old pad material and give the new pads room to bed. Also, you only have to remove the two TORX head bolts to remove the caliper; don't bother with the large (18mm head) bolts that secure the caliper mounting bracket to the spindle assembly. You only have to unscrew the caliper bolts from the bracket; don't pull them completely out of the caliper unless you for some reason planned to clean and relube them (once loosened they should move pretty freely, if not you might need to clean and relube). If you DO replace the rotors, the small allen head lock screw MUST be removed in order to remove the rotor and BE SURE to put it back; don't leave it out since otherwise the rotor has the potential to rotate independently of the hub. If you were to remove the tire (say changing a flat) the hub could then rotate and block or partially block the lug bolt holes. Not fun if it is dark and raining, so just put the screw back in. It will also stably hold the rotor in place as you refit the caliper mounting bracket and caliper; if it's flopping around that can knock the pads out of position and really irritate you.

PISTONS: The pistons simply press back into the caliper; no turning or special tools needed. However, unless you've religiously flushed your brake fluid, there will be lots of impurities in the line and you DON'T want to push those back through the small passages in the ABS system and master cylinder. Thus, instead of just pushing the piston back in (and opening the master cylinder), position the caliper with the bleeder screw facing up and at the highest place relative to the rest of the caliper, and then slightly crack the bleeder screw to loosen it (still want it a bit more than finger tight), place a hose over it to catch fluid (clear is better) and then open it slightly while compressing the piston. As the piston reaches bottom, close the screw and bottom the piston in the caliper. Retighten the bleeder screw and replace the dust cap. This will dump the fluid out of the caliper and won't introduce air or impurities back into the system.

PADS: There are lots of threads on here about pads; parse through them. In my case after reading through here and a Beemer forum I decided on the Axxis Ultimates. So far I've been very satisfied with them, good peformance and much reduced dust.

That's the high points, so take care and enjoy the ride.
Greg

Top Jimmy

OK borderline off topic, but why are your hands so clean, Greg?
You are the master.

Gregs210

... lack of brake squeal.

Actually -- I'm not ashamed to admit this -- nowadays I usually wear either mechanics' gloves (which I keep in the trunk in case I need to change a tire) or medical examination gloves when I do any significant work on cars. Long ago, in a galaxy far, far away, I used to wrench for a living and it took hours of scrubbing just to get them halfway clean, and for something like this it's especially nice. You get all the old stuff off the car, clean everything up, and then you don't have to worry about getting a dirty/oily fingerprint in the middle of a brake pad. Plus you don't have black under your fingernails for the next month and you get to find out if you're allergic to latex (keep it clean, guys...).

I'll try to get a post up (it will probably be several separate posts in a new thread) on my brake job before the end of the day.

Take care, and enjoy the ride.

JimE430

I will be doing the brakes soon as my drilled Bembos and pads come. I just flushed out the entire brake system and replaced with MBZ fluid. Do I still have to use the bleeder, or can I push the fluid to the resivour? My fluid is clean so I think this would be ok. Anyone know, LMK.
Jim

Richard Juarez

for the front pads I don't foresee any difficulties. Since i don't know what year/model of your MB. you may or may not need a brake caliper compressor which you can borrow from the auto parts store. This is incase your piston needs to be rotated back into the caliper. If not you can use a simple C clamp. As for the rear breaks you need to go into the cars menu to retract the pads. Then on the passenger side there is a pad wear sensor about $7.00
watch this YouTube video Very helpful. Good luck