Brake Rotor Question

Hi all,

So, I need new brake pads on my 2017 Mazda CX-5, and was informed that my rotors were in good enough condition to “turn” them. Should I do this, or should I opt for new rotors? I know that rotors have to maintain a certain thickness to “turn”, but I’m not sure if this is a better choice in the long-run. Can someone help me out with this decision?

Thanks so much!

Just ask them the price difference between turning and replacing . There would have to be a large savings before I would turn them . This also one of those decisions a person makes that does not cause loss of sleep.

Replace them.

The new rotors will have the proper surface finish so the new pads bed properly.

Tester

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One would have to depend on their expertise. If they think turning them would be fine and they are a reputable shop I would trust their decision, as I do not have the ability to make a decision one way or another. You can always ask the difference in cost for good new rotors vs turning the old ones and go from there depending on price and confidence level in the shop. EDIT: Sorry to repeat I type too slowly I guess.

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Thanks, guys! It is the Mazda dealership recommending turning them. I will find out the cost to just replace them.

You might also take the car to a local, independent repair shop for a 2nd quote.

You might be shocked how much cheaper the price is, compared to the dealer.

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Most shop that I have worked for, resurfacing the rotors was included in the price of the brake job. New rotors are $100 each. The cost difference is $200 per axle.

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Just as a side note it is nice the dealer is offering turning the rotors. We bought a used car in april and after a few long road trips would occasionally get a rumble in the brakes. Happened 6 to 10 times over 3500 miles. So they took me in the shop and there was much not sure how to describe it, bubbled up stuff on the outside of the rotors. High heat can cause this rumbling with rotors in this condition, got half off a $380 brake job. One never knows if one go a good deal or not, but I am happy enough. I wanted to let it go till spring after the salt season, but wife wanted it done so we did. Just trying to say one can not always have the perfect answer to any question.

Stock rotors are usually higher quality material. I would have them turned this time. next time go to an independent shop and replace with aftermarket to save money.

You do realize that Mazda doesn’t make brake rotors/pads?

They buy them from a vendor.

This may be Raybestos, Wagner, Bendix, etc…

So an aftermarket brake component that meets/exceeds the manufacturers specifications may be the same component that came on the vehicle at the assembly line.

Or better!

Tester

Yes, but the rotors they use are high quality using premium material. When I buy aftermarket I go to autozone and buy the mid-range. These rotors I wouldn’t turn, but I know the rotors that came stock are worth keeping through at least one turning.

Is that the customer pay price at the shop? OEM brake rotors for my Mustang (with the big 6 pot Brembos) run about $60 retail. Rotors for the customer’s vehicle run around $40-$60 retail.

Pro-Demand labor guide shows $99 for each rotor.

Front brake job on a Lexus ISF costs over $1,000 with OEM parts.

So is that what your shop charges regardless of what the actual price of the rotor is? Or is that what they say the price should be on average including mark up. If the cost for the rotor is around $60-$70, then a price of $99 (including markup) isn’t totally unreasonable.

I could see that, the IS-F was a niche car, and niche cars often have higher priced parts. The OEM rotors seem to go for $80- $170 at retail alone. With markup I would expect the price to possibly be upwards of $200 per rotor, add another $200-$300 for pads (they are pricey from what I been able to gather), a couple hours of labor and you’re there.

the way shop approaches the “turning” will affect both costs and quality

I’ve seen a shop doing on-the-vehicle-turning using a specialized/portable lathe

I would imagine the resulting surface will have virtually no deviations as the unevenness of how rotor is attached to the hub is already “counted it” this way, and surface is close to mirror in the end, so I would not expect any problems bedding in the pads

There’s nothing wrong at all with machining rotors as long as the minimum thickness is not exceeded and as long as the final few passes on the brake lathe are done slowly. I have seen a few guys never use a slow cut and make the final pass or two on the highest speed the lathe will run at. That gives a poor finish and should be avoided. There’s also the issue of whether or not the tech is keeping a sharp bit in the lathe as that can make a huge difference in surface finish.

Just my experience but it seems most rotors only have about .030 to play with when it comes to cutting them.
The rotors on my Lincoln have over twice that and those much beefier rotors are likely the reason there are no issues with them. At near 300k miles on the original rotors they have never needed to be turned nor do they show any run out or parallelism issues.

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When a set of rotors is within a few dollars of machining the old ones why bother machining I say. But when replacement is more than double the cost of machining and the old rotors will be within spec after cleaning them up I go for that option and for years I had a brake lathe that used abrasive discs that resurfaced the friction surface of rotors and left a ‘better than original’ mating surface while removing less metal than cutting them.

The #1 enemy of rotors is heat. If the original rotor is substantially heavier than an aftermarket replacement, it is better to turn. That being said, I usually don’t use high end rotors and would be a waste of time to turn the ones I use.

As always there is a great deal of professional discretion available in determining the “best” solution to repairing and maintaining automobiles and we each must take our best shot based on past experience @tcmichnorth. And yes, the OE rotors are often up to resurfacing while many after markets aren’t. And when in doubt erring to the side of caution is worthwhile. Comebacks are a great deal more costly than minor customer annoyance of the price.

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It’s true that carmakers don’t make their own rotors. They do usually spec a higher quality part than much of what’s available on the aftermarket. For that reason, it makes sense to keep the OEM ones as long as they are OK, and if they can be machined with good workmanship, do that. If and when they are too thin, or warped, it’s time for new ones.

I have found good results at a reasonable price with whatever rotors the people at NAPA say they use themselves, and poor results with some other aftermarket rotors. If money is no object and you want certainty, buy the OEM rotors from a dealer.