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Brake Rotor Turning

I am having all 4 brake pads replaced. If there is no indication of a warped rotor manifested in brake pedal pulsing and no groves indicated on the rotors, would I have to have the rotors turned?

The salesman at Midas says if I don’t turn the rotors I may have brake squealing. Is he just trying to generate some extra revenue?

Thanks,



Zorba

Probably. Another problem is that most late model vehicles have thin rotors from the factory. If you have them turned they may get hot enough to warp on their own. I also advise anyone to stay away from chain shops and find a good independent mechanic. If you have a problem with a brake rotor it’s best to just get a new one. They are not that expensive.

I assume that you mean all four wheels, which would be eight pads. Anyway…
I would either replace all four rotors or use them as-is. I would not waste money turning them. It costs almost as much to turn as to replace. After turning, they will be so thin (they start out pretty thin) that they are likely to warp soon and require replacement.

What you really want to know is what the thickness of new rotors is, what the thickness of your current rotors is, and how close those are to the minimum thickness. The minimum should be stamped on the rotor and would be in a vehicle repair guide.

If you are maybe only about halfway down or less on rotor thickness (just find the midpoint between new and minimum and compare to yours) I would probably just leave them alone.

If you are past the halfway point, I would be tempted to just replace them all. Turning rotors these days is just often a bad bet.

If you decide to keep the old rotors on there, then you can minimize the odds of squealing by fully “bedding” the new pads to the old rotors. They might seem smooth, but in braking terms they aren’t. You could spend a whole day figuring this out though, so you can just ask them to make sure to break in your new pads. Click & clack have this to say about it: http://www.cartalk.com/content/columns/Archive/2003/June/05.html

I’d replace them, but I worry what Midas will charge you for it. My problem with using rotors without turning or replacing them is that, even if they look ok, they’re now worn in a way that matches your old pads, but might not match your new ones, resulting in poor initial brake performance.

I have numerous times replaced only the pads where there was no indication of warping, scoring, or glazing without problems on my own and friends vehicles. Most shops won’t do this because because they want to prevent unanticipated problems and complaints. Frankly, new rotors can be bought for most vehicles cheaply enough to not even bother considering machining the old ones. Machining makes the old ones less capable of handling heat anyway. New car rotors are generally too thin to “turn”.

Midas, however, is another discussion. They do not have a good reputation in my area. My understanding is that they pay their techs comission on any additional work they can generate, and they become very practiced in “finding” SERIOUS work that you car never really needed.

I’d suggest finding a good reputable owner-operated shop and letting them change the rotors if they see fit.

The proper by the book repair is to surface or replace the rotors. Not servicing the rotors can lead to squealing, squeaking, or even vibration after the fact so the guy at Midas is correct.

Many times customers adopt the extra revenue mindset and a week or a month later when the brakes are making noise and shuddering they will then attempt to put this back off on the shop that did not service the rotors.
If a customer does not want rotors serviced fine, but any guarantee should be up the second the wheels are put back on the car.