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All good posts above. Kittens, since you didn't know what guide pins were, how about a quick and easy "Disc Brakes 101" to carry forward?

Pads: This is the primary wear component in any disc brake system, any car/truck brand. They are squeezed against the disc rotor by the caliper to stop the car.
Rotor: The shiny disc looking thing you can see through the wheel or when the wheel is removed.
Caliper: The hydraulically operated device that applies pressure to the pads to squeeze against the rotor, stopping/slowing the car.

Calipers center on the rotor by riding on lubricated guide pins. These need to be lubricated to make sure the caliper can freely center itself with the rotor and allow the inside pad and outside pad to wear evenly. Should the guide pin not be lubricated properly, the caliper can "stick" and not stay centered on the rotor causing one pad to wear faster than the other. When changing out the pads this is something to look for. If the wear is visibly uneven, chances are one or both guide pins is sticking and both should be removed, cleaned, checked for wear, and if good, lubed with the proper grease and reinstalled.

Rotors will eventually wear out. The pads wear faster, but depending on the material of the pad (organic, semi-metallic, semi-ceramic, ceramic) the rate of wear can be faster. The big question on rotors during a pad replacement is generally use as is, resurface, or replace? Well, that depends. :)

If the pads have not worn to the point of metal on metal contact with the rotor they can probably be reused IF they have not worn below the minimum thickness allowed. This is a dimension usually cast in the surface of the rotor. If they have not worn beyond or near that dimension, the next question is whether to "turn" or "resurface" the rotor. Note that if the rotor has not worn below the minimum thickness and does not have excessive rust within the fins (fins are for cooling, typically on the front rotors only and are between the inside and outside shiny surfaces) the rotor can be turned. If you are feeling a pulsation in the car or brake pedal when stopping and want to fix it, the rotors must be turned (if there is enough thickness) or replaced. As stated in prior postings above, this will also get rid of the wear ridge on the very edge of the shiny surface and can eliminate odd noises. If there are "grooves" worn in the rotor, turning will aid in the "seating" of the new pads. Here again, not a safety issue, more a "cheap and quick" vs "complete" service.

If the rotor is worn to or beyond the minimum thickness, or is grooved deeply to the point that resurfacing smooth would take the thickness beyond the minimum, the rotors should be replaced. This is a safety issue and deserves that level of attention.

So, to your original post, if the shop you used saw even wear on the removed pads, felt no pulsation in the brakes when applied, and the rotors were neither rusted out or excessively worn, then a simple pad replacement will indeed get you safe brakes.

The dealer quoted a "complete" brake job which should include quality pads, rotor resurfacing or replacement, and full cleaning and lubrication of all guide pins. Not that the dealer job in this instance would be safer, but in warrantying their work they want to be sure there are no noises, vibrations, etc that while not a safety issue could raise customer concerns.

Hope this is useful for our readers who are new to the world of automotive maintenance, whether a do-it-yourself newbie or to help in talking with a repair shop. To our more experienced folk, please feel free to add if I have missed something.

Peace
 

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One of the strangest noises I ever heard from a disc brake after the rotors were turned was a very loud "CLACK" that repeated loudly and slowed down with vehicle speed. Cause?

The fellow who turned the rotors didn't know what he was doing. Tried to turn to quickly, moving the cutting bit across the rotor surface too quickly. This produces a "spiral" cut like a record album. So when the brakes were applied the pads tried to follow the "groove" and would snap back when it hit the limit of travel. Darndest thing I have ever heard, and was spotted when the wheel was pulled. Really obvious. Had a different operator do a slow light cut and problem fixed.

:wallbash:
 
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