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I've driven a moderate amount for 2 days after I noticed the horrible sound coming from my brakes.

Do you think there is any chance I can still have them resurfaced? I realize the obvious answer is 'I'd have to see your individual brakes to answer that' but I just wondered if anyone has driven on them and only replaced the pads and it was fine??

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Squeaky brakes are often the wear sensor, when the pads get low on material they're designed to squeal so you know they need attention. So, you'll almost certainly need pads.

As to whether you need to replace the rotors it depends on their condition - just because you need new pads doesn't mean the rotors will absolutely need work, they may be fine but you have to check:

  1. You need to measure how much material they have left with a rotor measuring tool and see if they are still within tolerance. If they are out of tolerance, i.e. too thin then they'll need replacement. If they are just over tolerance it's still a good idea to replace them
  2. If they are warped then they can be resurfaced provided they are going to still be thick enough at the end. It really depends on how warped they are, if they're really bad then replace them. You'd probably notice uneven and wobbly braking if this was the case
  3. If they are badly scored or pitted it's best to replace them
  4. They may be fine other than a raised lip around the edge, in which case you can buzz it off (carefully) with an angle grinder
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    Some brake pads don't have "squealers" and the first time you hear the squeal for those it is a good idea to (read as "required that you") replace the rotors also. Always buy the squealers in my opinion - you have a choice when you do that. Commented May 3, 2022 at 20:38
  • Squealers are good, plenty of cars have electrical sensors instead now. Typically if you wear pads down to the metal you're going to see it clearly on the rotor.
    – GdD
    Commented May 4, 2022 at 7:45
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Always turn or replace the rotors.

At the very least, the rotors need to take a trip to the machine shop to be "turned" (surfaced)... because you need to check it for being warped, and remove surface blemishes so the new pads work properly. Putting new pads on a worn rotor is just asking for trouble.

A great many rotors are inexpensive enough that they are cheaper than turning (or cheaper when accounting for the mechanic's time sending them out and having your car on the lift the whole time, since the car's brakes must not be touched while the rotors are off, and that would be all too easy to do while moving it around the garage).

Also, some argue that the chance of hidden warpage is not worth trusting a used rotor, and just do new everytime on general principle. Not me - I have a pile of "used once" rotors because every brake job I am finding new rotors < labor cost of turning this time. I'm not a quick learner lol.

So you don't have to replace the rotors, but you must do something... and that usually adds up to "replace the rotors" lol.

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  • You don't really have to have the car wait on the lift for the rotors to be turned. Just replace them once with new ones, then take the old ones with you and send them to turning at your convenience (potentially shopping around for best price), then store them for the next time you need to replace rotors. No additional mechanic time needed.
    – TooTea
    Commented May 4, 2022 at 12:35
  • Especially newer cars also use thinner rotors that don't turn that well anyway - in addition to being cheaper than a machinist. They're meant now to generally just be replaced rather than removed and turned. For older, classic, or certain specific vehicles it can still make sense to turn the rotors, but for most modern vehicles it's just not worth it.
    – J...
    Commented May 4, 2022 at 16:28
  • @TooTea I was thinking of a customer taking a car to a mechanic. Mechanics won't want to install your used part of unknown provenance, that's just asking for a problem. Commented May 4, 2022 at 20:20
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You can just replace the pads, but you won't get the best performance out of your brakes in doing so. You need to inspect (or have inspected) the vehicle to see what is going on. Lots of times when you hear an obnoxious noise from what sounds to be the brakes, it is the "squealer" (small metal strip on the brake pad) which, when the pad gets thin enough, comes in contact with the rotor and starts making a squealing noise (thus the name). When you get to this point, you really need to start thinking about getting the brakes replaced ... if not only for the safety aspect, but for your sanity as well (listening to the squeal will drive you over the edge ... pun intended :o)).

The best route if the brakes need to be replaced is to replace both the rotors and the pads. I personally find this easiest, as well as take less time to get it done (since I'm doing it myself). If you are mechanically inclined enough to do the job, then you can change them out without too much hassle. It saves a trip to a shop to have your rotors turned, as well as allowing you to do the work on your time and not pay the shop costs in the process.

The next best is to have the rotors turned and the pads replaced. If you have a shop do the replacement for you, they'll tell you whether or not there is enough meat left on the rotor and can advise you on replacement or turning, whichever suits your needs.

The next option is to replace just the pads. I HIGHLY recommend you do not do this, as your stopping power is greatly diminished. Could it get you by in a pinch? Sure. It's better than going metal-on-metal in your brake system, but only because you won't be damaging parts while using them. You're not really doing yourself a favor, or your car. More than likely you'll burn through the pads much faster than you would with fresh surfaces on your rotors, but it can be done.

Your final option is to drive it as it is until the wheels fall off. This really isn't a "viable" option, but it is an option. I'd highly recommend against this option as well (for painfully obvious reasons). If you were to make a choice like this, you're not only making this choice for you and your car, but for any passengers and possibly other vehicles/drivers/pedestrians around you. This would be a very negligent option.

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    The rotor does not need to be replaced every time you replace your brake pads—unless you damaged the rotor by running your brake pads down to the metal. Also, the wheels don't fall off if you run your brake pads out. It's likely you'll lose brake fluid pressure and lose all braking power. Commented May 3, 2022 at 20:26
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Just look at your rotors.

Since you have rotors and not drums, the working surface is visible, with some creativity - from both sides.

Clean, shiny surfaces on both sides of each rotor = rotors are usable, provided they have enough thickness as well.

Deep circular traces, rough surface, deep wear = replace both rotors.


p.s. yes, I did once replaced only pads on scratched rotors. This is neither to be recommended nor repeated, but the rotors "recovered" after some mileage.

Doing things like this profoundly depends on how much experienced and conservative driver you are.

Driving safely a broken car is a rather demanding task and requires rather high mechanical literacy and general IQ.

If your ABS kicks in more than once in a year, do things by the book.

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Without looking at them, I'd default to saying pads and rotors. I've had great luck with https://www.partsgeek.com/ (I'm not paid by them, just a happy customer) and they sell very reasonably priced sets.

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It would be best to replace the brake pads and rotors at the same time. This will ensure the pads and rotors last longer and will provide better braking performance. The cost difference is usually not that much between resurfacing and purchasing new rotors. As of late some car manufactures have reduced the thickness of the rotors to save weight to meet federal gas mileage standards. I would suggest replacing the pads and rotors. As @Mr. Anderson has indicated there are a number of online web sites offering better pricing on brake pads and rotors versus brick and mortar auto retail stores. If you are not going to do the work yourself there are mechanics that will allow you to provide the parts and they will replace for you. Be aware that they will not warranty the brake components, but the manufacturer should provide a warranty for the parts they sell.

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It depends. The noise could simply be the wear guard rubbing on the rotor and a simple replacement of the pads can solve that (although, I would still at least turn the rotors to make sure they aren't warped, etc.). If it is more of a metal grinding noise, then there is a good chance that the pads are totally gone and have eaten into the rotors. In that case, it depends on how deep the damage is as to whether you can have them turned or you need to replace them. Some shops won't turn rotors any longer because they are so thin to begin with and replacements can be cheap, depending on the make and model of the car.

In the end, I recommend just replacing the pads and rotors because brakes are one of those things that you don't want to skimp on.

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You said "horrible noise"; check them as soon as possible because if the pads are completely gone, the remaining metal will wreck the rotors rapidly (that's personal experience talking here). I've always turned rotors with the hope that that is more planet-friendly versus 'making one from scratch'. Whether a rotor is turn-able depends primarily upon its remaining thickness, measurable with a caliper. Note that appearances can be deceiving as a rotor can be warped, which would benefit from it being turned/resurfaced.

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