MIDAS Brake Job

My wife's '98 C230 recently needed a brake job and I called the local M-B dealer for an appointment and to reserve a courtesy loaner while they did the work.
"We don't provide loaners for brake jobs" I was told.
Hmmm. Well, that's awkward. She works 60 miles east of me so there is no chance I could drop her off and pick her up and try to "make do" with just one car for a day.
So I swapped cars with her and called the Midas dealer closest to my office. They agreed to deliver me back to where I work, so I took the car over and everything worked out great.
Except for one thing.
The friggin' Bendix pads they used began to squeal so bad after 3 days my wife refused to drive her car.
So I schlepped it back to Midas.
No argument. They re-did the job at no cost to me. The write up guy explained "We used 'original equipment pads' this time." Great.
Four days later she tells me they've started screeching again.
To today I took it back the THIRD time!
They did the job again and they were very nice about it.
The write up guy called me at my office and said they'd put it all back together again and test drove it and it STILL squealed! (On the original job a couple of weeks ago they resurfaced the rotors and installed new pads on both axles. The brakes hadn't squeaked a bit prior to taking it to Midas...so this is all brand new.)
After he gave me the bad news today he said he was going to have to "Call Midas Corporate" to get permission to go to the Mercedes-Benz store and buy some genuine M-B replacement pads. I asked what that meant - since they'd already installed 'original equipment pads' and he explained "Well, yeah, they're supposed to be OEM but we get 'em through the same warehouse that we get the regular aftermarket ones - in other words they don't come in a Mercedes-Benz box."
Oh.
"So now we want to get that kind."
Oh. Yeah. Me too.
I don't know if I'm going to get another call from him tomorrow telling me that 'Corporate' told him he couldn't buy the real thing or not but I'm bracing for the worst and keeping my fingers crossed.
Any thoughts? (Don't remind me that maybe I should have taken it to M-B myself and took a vacation day so I could wait in their service lobby.)
Pat
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As long as the pads are decent, squealing isn't the pads fault. Tell him to forget about getting the MB pads, it'll be cheaper to get PBR metal masters from www.buymbparts.com, plus I like them a lot better (though maybe no, because they have a higher chance of squealing than Benz ones, they just stop better and put out less dust, so I like them). The trick is to make sure he gets a lot of anti-squeal paste on the backs of the pads, and maybe even put shims on back of the rear pads. Then they won't squeal. If I had to guess, if they remembered to use anti-squeal paste, then the problem actually probably has to do with resurfacing the rotors. Benz rotors are soft enough that they generally don't need resurfacing. Richard

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.>The trick is to make

maybe
I still have never understood how paste and shims will prevent brake noise on systems that have the pads secured to the caliper. On some older systems I've worked on, the pads aren't physically attached to the caliper, so the paste and shims are required to keep the pads secured and prevent chatter, but exactly what does this do on systems like MB where the pads are securely attached?
BTW, on my last brake job, I used Rotex pads (would never use MB pads, too much dust and too weak). I have one that squeals, but only when the pedal is gently pressed, such as when first beginning to slow in traffic. Once the pedal is pressed harder, the squealing stops. I examined the pad and found an unusually large fragment of metal molded into the stock. I smoothed it with a Dremel and the squeal went away for a few K miles, but it's back now. Looks like I'll have to either live with this until the pad wears beyond this large fragment, or get a lot of practice dismounted the tire and using the Dremel.
--

- RODNEY



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systems
securely
I don't see how Benz pads are secured to the caliper. To the best of my knowledge, on most MB's, the brakes are held to the caliper by having to metal rods go through both calipers and both pads. This still allows for small amounts of back and forth motion, so the shim and paste dampen that. Richard
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noise
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chatter,
On the ML, the inner pads have a "flower" shaped clip that pushes into the hollow center of the piston, thus securing it. While there is some play, it's not much at all, maybe a few mm's at the most. The out pads also have clips on the back so that they to be slid onto the outer caliper frame. There is *no* play in this connection at all. In fact, is sometimes a bit of a PITA to get the outer pads off the caliper if they have been on a while and gathered some oxidation.
I recall having very similar configurations on other vehicles (mostly MB's, maybe one BMW or Audi). I noticed Toyota/Lexus uses a spring clip on the side of the pad that helps to hold it into the caliper, but it still allows for some movement, so brake paste is usually desired. On one car I had (don't recall the brand, but not an MB), there was nothing holding the pads to the calipers. They literally floated between the caliper and the rotor and if they were not held in place with adhesive shims or paste, they would chatter and break.
Of course without some method for securing the pads to the caliper, I will definitely agree that some sort of adhesive is necessary, but with the system on the ML and other modern vehicles, I still can't understand what purpose it would serve. And by the way, I am not being argumentative - as a shade-tree mechanic with no formal training, I am truly trying to understand what the paste does, other than keep the pads from chattering.
--

- RODNEY



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To be honest, I'm not too hip to these newer brake pad retaining systems. As far as I know though, even a tiny bit of vibration will cause the pads to squeal, and the past dampens the vibrations. Richard

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to
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maybe
Shims only on the rears?
Pat
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It's not so much only shim the rears as it is make sure to shim the rears. Basically, I'm NOT saying DON'T shim the fronts, but I AM saying DO shim the rears. Richard

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If Midas said no, then tell them to go buy Raybestos QS brak pads at Pep Boys, etc.
I personally would not use MB pads... MB pads will squeal if not properly broke in. A shop did it for my folks.... all new rotors, all new MB pads... and guess what? Squealed like a friggin pig... so loud that even I can hear it. Will scare birds away for a mile.
Any pads will squealed if not properly broken in. Tell them to rough up the rotors with medium emory sandpaper... put new pads in... and break it in right... which they don't know either...
How? 40 MPH or higher... slightly step on the brake to slowly slow down the car to 30... or 40... only 10MPH slower is all we want to do... then let go of brake and accelerate until 40 again and repeat... do this 4 times and you are set for life.
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I also had _really_ squeaky brakes until recently- they too, would squeal only under light pressure (as when semi-rolling, semi-braking to a slow stop at a stop sign or red light. Little kids on the sidewalk would cover their ears. I mentioned it to 'my' mechanic at the recent 168,000kms service, and even suggested that he change out the pads for new ones, (pads and rotors were replaced two years ago at 97,000kms) but he reckoned that it was being caused by a build-up of the infamous M-B black brake dust, and that putting paste on the pad backing wouldn't be of much help. He did a good pressure wash of the pads and rotors, and fingers crossed, knock on wood, thumbs pressed, they haven't squeaked in the 4-5 days since. Although it's unlikely this would be the cause of the original poster's brand-new Midas pads squeaking, a good blast (and drying, of course) might be worth a try for the higher mileage squeaking squealing creaking pads.
John M. '94 E320 (stealth version)
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A stealth version? How do you find your car in the parking lot?
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