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Rotors and brakepads

My 2004 car recently passed its annual inspection and the mechanic told me it’s in great shape but that I need to have my rear brake pads replaced, especially the rotors. He recommended getting it done within the next 30 days. He’s not my regular mechanic, so I took it in for the replacement but I keep hearing a grinding sound on my rear left wheel. Would it be strange for a mechanic to replace the brakes but not the rotors? I mean, wouldn’t he see what the inspection guy saw?

What did you pay for? Replacement pads and rotors should be listed on your bill. They could machine the rotors rather than replace them but that is not common anymore.

If you hear grinding, take it back to the place that did the rear brake job.

Without seeing the repair invoice answers are not going to be anything but guesses . As soon as you hears the grinding you should have notified the mechanic. There is a period where the repair and parts are warranted. Did you have all the service brought up to date on this vehicle you bought about a year ago ?

Brakes and rotors have gone hand in hand for me.

Yeah, I was trying to figure out if it was odd that the rotors wouldn’t have been replaced given that the guy who did the inspection said they were worn out. I did call my guy last week & mentioned the grinding & he said I had to drive the car a bit to break the new brakes in & that the grinding noise should go away but it hasn’t. I like my mechanic but it makes me nervous that the rotors wouldn’t have been replaced, which they weren’t based on the invoice.

Take it back to the mechanic. Grinding could mean the pads weren’t installed correctly and are constantly making contact. Check your invoice and see what exactly did you pay for. Pads & rotors or just pads. In any case, you should not hear a constant grinding.

Did the inspector record the rotor thickness measurements on the inspection report?

I installed rear brake shoes on my Corolla last spring and that created some minor scraping/sandpapering noise at first. It took about a month’s driving for the sound to go away.

I have occasionally seen where a guy had a brainless moment and installed a pad backward. The backing plate against the rotor can squeal or grind, or both. You definitely need to take it back in.

And btw:

Bull. After a properly-done brake job, the brakes should not grind. If they grind, something is wrong. The only exception is if the rotor rusts overnight from humidity, but then it will only grind the first couple of stops as the rust layer is scraped off, and then it should be quiet again.

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Thanks so much, I put a call back into him. Really appreciate this community. I’ve gone my life without ever needing a car because I’m a city kid, but recently inherited a gem from my aunt and am doing my best to take care of it and when you don’t know anything about cars, it can cause a bit of anxiety!

Properly done is the key word. He’s telling you to wait because he didn’t replace or even turn the old rotors. He’s expecting the pads to bed into the existing grooves/deformities of the old rotor surface. You say the bill doesn’t mention new rotors, does it have any mention of machining the old ones? Bet not…

It doesn’t say anything about rotors. just brakes and calipers.

Did you tell him to replace the rotors?

If you did, and he didn’t, that’s not OK.

Assuming you didn’t specifically say that, he may have determined that it was not necessary to replace the rotors. That’s fine too, but the surface should have been machined unless it was in great shape… Which apparently it wasn’t because it’s grinding!

No. I rarely replace rotors. Only when needed. I’ve owned a few vehicles with original rotors or drums on the vehicle when I sold/gave-away with well over 300k miles on vehicle. Rotors were fine. No pulsating of brakes, and vehicle braked as well as when new.

I get 80k out of brakes and had 2 brake jobs 85k, and 160k, at 200k now. Did not mind spending the bucks for new rotors.

Have the mechanic that did the brake job put your car on a lift and remove a back tire. If the rotors are scored, they weren’t replaced or ground. If the calipers don’t look nearly new, they weren’t replaced. Have him show you the pads if it doesn’t look like the other parts are new or refurbished. If they don’t look new, they weren’t replaced. Do this with both wheels if the first wheel looks suspicious. There is no excuse for putting new pads on rotors that aren’t flat and completely smooth. BTW, unworn brake pads are about 12 mm (half inch) thick.

A few suggestions

  • Popular Mechanics Complete Car Care Manual explains pretty well how everything works in modern cars, including the brakes. Suggest to secure a copy for yourself. Many bookstores carry it, and do many public libraries. The key to auto problem diagnoses for the armchair diy’er imo isn’t following some cookbook list of step by step procedures; instead, focus your efforts on understanding how the part or system that is not working is supposed to work.

  • Choose your mechanic/shop by asking friends, relatives, anybody you have a personal connection with who they use to fix their cars. Then interview 2 or 3 from that list that specialize in your make. Make sure to tell the owner of the shop the name of your friend that recommended the shop to you.

  • Taking car of the outside of your car is pretty easy, something you can probably do yourself. And will pay dividends in keeping it in good shape and good appearance. Rinse your car off with a garden hose every week; wash it with soap and warm water only when it gets really dirty; and wax with an easy on - easy off wax twice a year. All that takes very little time, so you get a good bang for the buck.

Will you just stop with that nonsense . That may work where you are but in my area all that will do is leave ugly water spots .