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Mercedes Benz ML320 replace or resurface rotors

The service consultant at my Mercedes dealer said he double checked but they had to replace the rotors of my 2001 ML320 with 56,000 miles. I told him that the rotors of all of my other cars were never replaced but routinely resurfaced by other dealers. I told him that the brake handling felt and sounded just fine. He said that the dealership replaced the rotor because resurfacing the ML320 rotor is a health hazard. I was able to get 3 out of the 4 rotors. The rotors don't look as bad as the rotors of my others cars. I hate to think that my dealer made a mistake but with a $1,200 front/rear brakes plus rotors I feel like I was born with the mark of a sailboat on my forehead. Does anyone know if Mercedes dealers routinely replace rotors, instead of resurfacing rotors, because of the health hazard? Thanks in advance for your help.
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Comments

  • edited September 2007
    Health Hazard ?

    Did they specify what the health hazard was, I've never heard of that one...

    I know MB do not recommend resurfacing their rotors, they are vented but do have a minimum rotor thickness stamped on them, provided the resurfacing does not exceed the engineering tolerances, I don't see the problem.

    But as I said, MB recommend replacement. Maybe the health hazard is possible brake overheating on steep hills.....I'd agree that could be a health hazard.

    I'd be interested in their answer though.
  • edited September 2007
    Like most people, when you walk into the dealer you will be talking to a service advisor. Most SAs are not mechanically inclined but you would not know it by the bilge they spout; such as here.

    The only health hazard when machining rotors is if the tech drops a rotor on his foot or gets his shirttail caught between the rotor and brake lathe cutting bit!

    Rotors on most late model cars are thin and there is not much to cut. Cuting rotors below the minimum thickness spec makes it a safety/liability issue.

    Also, the cost of machining (flat rate time X shop hourly rate) makes it prohibitive and it's more cost effective to replace them rather than spend money machining and wind up with thin rotors.

    Hope that helps 'splain it anyway. :-)
  • edited September 2007
    I assume they meant "safety hazard." In general, benz recommends not resurfacing rotors and replacing them with every set of pads. In practice, most independents will let them go for two sets of pads if the still meet the thickness specs and are true. It is usually cheaper to replace them than resurface them anyway.
  • edited September 2007
    It is common practice at both Mercedes dealers and most Mercedes independent shops to replace the rotors rather than resurface. As Craig said there is not enough of a price difference. If I have to warranty the work, it only makes sense to use new rotors.

    Benzman
  • edited September 2007
    I will ask my other "trusted mechanic" to check the minimum rotor thickness stamped on them whether resurfacing will not exceed the engineering tolerances. I know it's now an exercise in futility but I just have an inquiring mind and a lighter wallet.

    Health hazard per service advisor comes from the dust generated by resurfacing the special material of the rotor. I just wanted to shake my head in disbelief.

    I didn't have any choice but go along with their recommendation because I didn't want to take any unnecessary risk. I go to the mountains once a month on a winding and very scenic two lane highway over 8,400 feet high. If I enjoy the view too much while driving or if the brake overheats, the car will have to be replaced prematurely if I would be so lucky. That is why I bit the proverbial bullet for the recommended routine $1,200 repair.

    Thanks for your reply.
  • edited September 2007
    Very funny ok4550, I almost dropped a rotor on my foot.

    I just found a website that repeated exactly the same things you said:
    http://www.clipclip.org/clips/detail/1859/mercedes-brakes-mercedes-brakes-tech-tip
    Mercedes front brake disc last about 50,000 miles. All rotors, front and rear, are stamped with a minimum thickness allowed but we do not recommend resurfacing them. Replace them! They are inexpensive.

    I also found several websites quoting the price of rotors.

    Thank you ok4550, craig58, and benzman.
  • edited September 2007
    Here's another source for rotors, including cross-drilled fronts, if you want to spend a little more:

    http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.mercedesshop.com/&cookieid=1CQ0J3JZ426M1D2KJ2&year=2001&make=MB&model=ML-320-001&category=N&part=Brake+Disc
  • edited September 2007
    The web site makes has good advice about the pads as well. I recommend using only the Textar in the yellow box. World-Pac can get them over night for any model. They are softer pads, and will not get as many miles as some, but they are factory approved. You will have to wash the brake dust off weekly to keep things sharp, but that's a good thing. I've noted that a Mercedes that doesn't produce brake dust is a sick Mercedes.

    Benzman
  • edited September 2007
    Also, I've found some of the after-market pads squeak considerably more than the OEM.
  • edited September 2007
    Replacement is typically cheaper or on par with resurfacing rotors.

    In the yesteryear and also current antiquated brake designs they use thicker rotors leaving the possibility for machining. However the thinner rotors not only weigh less however also dissipate heat much quicker allowing for significantly better braking power.
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