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Turn rotors?

Dealer says rear pads on my 2008 Hyundai Veracruz Limited AWD are down to 8mm and should be replaced soon. My regular mechanic says turning rotors is needed as well. Question-is it necessary to turn rotors if we are not yet down to metal?
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Comments

  • edited March 2011
    Rotors are all metal, so I'm not sure what you're asking.

    If you replace rotors, and then turn them, what you are doing is shaving perfectly good metal off of a brand new part and therefore significantly shortening its life.

    If you turn rotors without replacing them, what you are doing is making the rotor thinner and therefore more prone to warp, which is why you turned them in the first place.

    In short: I just replace rotors. They're cheap, and it lets me go longer before I have to fool with the brakes again.
  • edited March 2011
    Rotors are made entirely of metal. The PADS are not. On any brake job the rotors should be "turned" or machined smooth in order for the new pads to seat well and wear evenly. Today's rotors are thinner and lighter and usually are replaced after the second turning.

    A good brake shop will do these things since they don't want you coming back saying that the brakes squeal or stop with grinding noises and vibration.
  • edited March 2011
    Most rotors are so thin these days it's not worth turning them. They will be too thin afterward and prone to warping.

    If the rotors need work, replace them. If they're not badly scored you could probably just put new pads on and leave them alone.
  • edited March 2011
    I agree but then again I use a lot of aftermarket parts and do the work myself.
  • edited March 2011
    Check your owners manual. If your brakes have wear indicators, they'll make noise when you need new pads. At that point I'd replace the pads and the rotors, just get good quality ones.
  • edited March 2011
    Thanks, all. the manual says that we have wear sensors, so we will keep an ear out for that screeching noise....
  • edited March 2011
    The philosophy behind turning rotors is to remove any uneven surface to provide the longest life for your new pads. If they feel the rotors can be turned do it, it will provide the best braking.
  • edited March 2011
    [b] Today's rotors are thinner and lighter and usually are replaced after the second turning. [/b]

    More often today it is recommended to replace the rotors every time you replace the pads. The difference in price is just too little to try and squeeze a little more life out of them, only to end up paying to replace them soon anyway.
  • edited March 2011
    DOWN to 8mm??? 8mm is right around half life for a typical set of brake pads. You probably don't have anything to worry about for another 20k miles or so, unless you are very hard on your brakes. If you like to wear your pads down to the metal, at that point you will probably need to replace the rotors anyway. Grinding the brake pad backing plate into the rotor will destroy it in very short order.
  • edited March 2011
    Nobody turns rotors anymore.

    First, the cost of turning a rotor almost equals the cost of a new replacement rotor.

    Second, as mentioned turning rotors makes them thinner making them more suseptable to warping.

    And third and more importantly, when the rotor is turned there's no way that the proper finish will machined onto the rotor so the brake pads properly embed into the rotor. This then causes brake noise.

    That's why nobody turns rotors anymore.

    Tester
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