Picked up my car today from the mechanic after changing brakepads, I expected them to machine or change my brake rotors due to my old brakepad's metal backing scraping the rotor but to my surprise the brake rotors look untouched.
(UPDATED) Photo of damage: Photo
The car feels fine to drive and brake but is it safe to drive with this damage?
We’re you advised by mechanic to have them machined at all?
Preventative maintenance is cheaper than repair.
Personally I’d of had it done, but to each their own I guess.
Dude, I am not a very car person, But I did manage to change my car's own break pads, and rotors by looking at YOUTUBE videos.
Dont bother machining rotors, its cheaper to buy new rotors than to machine old ones (especially in long run). I got the protex ultra rotors, and bendix breakpad, But if you find Repco generic Proselect brand ones cheaper buy those ones (Ceramic break pad, and coated rotors are better options)
Just had to buy stuff from online. and ALSO need tools, e.g. the screw unlockers,
(Pro tip: YOU SHOULD BUY A BREAKER BAR if you want to unlock the rotor bolt).
If you add it all up, with all tools and etc. it will cost you about same amount as getting the job done at mechanic.
BUT you keep tools after job, and LEARN.
if you dont change/machine rotors and just change break pads, you risk early damaging those break pads (because they aint rubbing against smooth surface)
Here's some videos you might find useful if you choose to change it yourself
https://www.youtube.com/watch?v=6RQ9UabOIPg
https://www.youtube.com/watch?v=Yma7MX-Euh4
I still remember that time when I didn't even know basic from what point do I lift/jack the car up from
Brake
Rotors last a few sets of pads. You change them when they are thin, like pads. You don't need to machine rotors unless they are warped/uneven (you'll notice it affecting handling), but you might as well replace them if you reach that point so you have a thicker (longer life) rotor.
Rotors last a few sets of pads. You change them when they are thin, like pads
This hasn't been the case for a quite a while now, and with euros, even longer.
My rotors are pretty new as this is the first brake change. I think I'll just accept the increased brake wear this time around and keep an eye on the thickness of the brake pads. I'll go with new rotors next time around.
Do you know price difference between machining rotors vs you buying (and supplying at very least) your own brand new rotors ??
If you do you wont be making such mistake.
Repco has cheap non coated basic TRW branded rotor starting at $5 (even though it aint as good as a coated rotor, but way way better than the image you uploaded)
@DOGGYWOWWOW: If I was you I wouldn't think twice, on buying new rotors for $5 each (if you able to get stock for your car). If you wanna doubt even spending $10 extra, dude you are in another world. Congrats.
@USER DC: Do you have a link to the rotors you're talking about? I can only find TRW rotors for $55. Maybe it's a different size.
@DOGGYWOWWOW: https://www.repco.com.au/en/search?q=brake+roto%3Aprice_METR…
you'll need to research your cars part number
You don't need to machine rotors unless they are warped/uneven (you'll notice it affecting handling)
So much rubbish in this statement.
In what way do brakes affect handling? brakes affect braking.
Discs should be machined if there is any visible damage.
Rotors are so cheap these days. I just bought rear pads, rear rotors and an airfilter for the Accord Euro. $103 delivered
Handling is how the car responds to driver inputs, typically this means acceleration, cornering and braking.
…breakpads are for dancing. What are "the screw unlockers" and describe a "rotor bolt".
Brake Pads are for OP's vehicle.
"The damage looks very similar to this" is not the actual Fault exactly. It is only similar. Plus it is only some of the information - damage - a mechanic requires to answer with accuracy…so how can you? Ever heard of Min thickness? Describe a Hot Spot? What is Warp Tolerance?
Ever seen a Hairline Crack? Which rotors are Not Machinable?
Hint to all non mechanic readers. Not every non mechanic or untrained/unqualified poster has the experience or knowledge to state a definitive answer. Stereotyping answers can prove to fatal if incorrectly applied in some scenarios. They may have only perhaps seen barely a few different brake repairs in their life.
Learning to do their/your own limited vehicle maintenance is great. BUT… Brakes are an essential Safety System, and not every simple diagnosis, option or repair method from their limited experience will suit your situation.
Please be careful giving and receiving advise. I have over 40yrs in the Trade, and even I would not say a definitive answer without correct photos, more information, and even then maybe not until seen in real life. Too many variables.
For the record, changing pads without machining is physically possible. The question is…is it safe?
"the screw unlockers"
The specifics tools that person needs to unlock bolt/screws, e.g. often one will find like Torx Male bolts ( I had in my Barina), thus I needed the corresponding female torx bolt (E13 or something like that) to unlock that particular bolt.
and describe a "rotor bolt"
To take of the rotor you would need to take some bolt before that which screws either rotor to wheel, or may be the bolt that screws brake calliper or the break pad holder, which is screwed to wheel or something there. I think it was this one which is like super tight, (Highly torqued) so need a breaker bar for that as ordinary rachets will not unlock those bolts. (Basically need to watch your own car videos to know what type of screws are there that need to be unfastened and torqued (and torqued to what specs)
Learning to do their/your own limited vehicle maintenance is great. BUT… Brakes are an essential Safety System, and not every simple diagnosis, option or repair method from their limited experience will suit your situation.
Watch what ChrisFix said.
I haven't given any false info (other than typo of break vs brake)
So 'screw unlockers' are just …Oh Tools. Torx Head Bolt…not Torx Male bolts. Rotor bolt is…well only on some assemblies and is actually a cheese head set screw.
"…..which screws either rotor to wheel, or may be the bolt that screws brake calliper or the break pad holder, which is screwed to wheel or something there……" These are never attached to a wheel.
A Rotor sits on / fits /locates onto a hub, or the rotor is integral with as part of the Hub one piece Assembly. Hence some loose Rotors are located with a set Screw, or assembled loose and secured by the rim nuts. A brake Caliper (no such thing as break pad holder) is never screwed to a wheel but it is bolted to the Stub Axle/Steering Knuckle/Spindle(it has various monikers). Don't forget the rotor puller / pusher bolt kit, and if you need a breaker bar you have other / corrosion issues. What of issue of hanging Calipers by the flexible Brake Hose?
The correct terminology when you are advising someone with no idea of Braking Systems is often critical as are Torque settings, Single use Security Bolts & Fittings, Brake Pad Glues / Anti Squeal Lubricants and Mating parts Interference fit Anti Seize compounds.
If you understand and comprehend fully the above, then it is just sheer good luck you are still with us and inexperience led us up the garden path. Otherwise, again I say… Let the experts advise on Vehicle Critical Safety systems. Incomplete and poorly written info is as bad as False info. A back yarder alone should never teach another back yarder. Learn and do it yourself by all means, just get the correct advise and teachings first, along with a Qualified Mechanic to check your work… remember, you are not even an Apprentice's oily rag and they are watched over by hawks in the workshop learning the many and multiple variances in a vehicles braking system.
ChrisFix said" my mustang brakes are similar if not identical to most other makes and models"…. seriously dude? They will only be identical to an unmodified exact same vehicle and model spec vehicle as his American delivery Mustang. Dude, you are in Australia… not everything is the same as in general purpose yank vids. Stating this back yard vid will teach you everything you need to know is a legal nightmare waiting to happen. When you crash and kill someone, this will Not be a Defense in Court.
You and I will never agree, so end of your thread perhaps.
Its fine, they just need to break in the new pads with old rotors.
If you do the work yourself remember to grease the rotors to stop them from rusting.
I would never grease the rotors because it could get on the friction surface and cause problems. I do put a thin layer of high temp grease on the hub surface to stop the discs getting stuck to the hub.
What about the Pad Heel & Toe?
I put a thin layer on the hub, and a layer on the back of the pads where the pistons push on them. All I've ever done and never had any brake noise.
It’s not fine, if yours were anything like the photos, that rough area will chew out the new brake pads very quickly. You should always get a surface machine at a minimum or new rotors are a better option.
The old pads will have worn the disc with high and low spots across the face. The constant heat cycling can also put surface cracks on the rotor faces or even cause slight warps in the discs.
So, can it be done? Yes. It “can”, but shouldn’t.
And to all the people voting “yes, it’s ok”, let me know when you are selling your car so I know what ones to avoid buying.
I uploaded a photo of my damage here: photo
I took the car for a drive today and the brakes seem fine with no shudder even under heavy braking. But I'll still take it back to the mechanic on Monday just to be sure. What do you think? Should I get new rotors now?
Every time i've ever had a mechanic do brakes they have always quoted to machine the disks or replace rotors. Not sure why they wouldn't as its extra revenue for them. Sometimes I've been too cheap to do it but always known that was on me
What is the thickness of the discs where the pads touch? And is that thickness more than the minimum permissible for your specific car?
Looking at the pic, machining those discs are not going to assist because the outer rim of the disc is too eroded. The bulk of the disc looks fine though. So I can see why he just put new pads on.
Out of interest, how did you manage to have the pads wear so much?
Maybe they had too much work on that day to do it? The mechanic should have said something.
A mechanic said they usually machine the rotors, as they make more money than replacing them (plus some rotors may not be in stock on the day).
Sorry this is not my picture but the type of damage is similar. My discs are definitely more thick since this is the first brake change but the edge is similarly scraped.
I uploaded a photo of my damage here: photo
That previous picture is similar but was off the internet. The rotors scraped for about 50km of driving, caught me by surprise as thought there would be the squealer noise to indicate thin brakepads before they run out.
Is it safe? Yes
Will that type of damage to the disc wear the pads out quicker? Also yes.
That's very unprofessional job. I'm not sure why you'd accept a half done job like that on a relatively new car.
There's a lot of really inaccurate and dangerous statements in this thread from people with no training or experience.
I agree. Simple really. The rotor is damaged and should have been replaced, along with the opposite side. Never replace just one rotor. These days, replacement is usually cheaper than machining. Rotors are now made with very little extra to allow for machining anyway. Another tip is to use a softer compound brake pad if allowed on your vehicle, as the hard ones shorten rotor life quite a bit.
That is not acceptable.