Since the day I bought it, my van has been a little noisy when braking. It stops fine, so I didn’t think anything of it. “Auto lift Tom” @TLAR was helping me out with some stuff and happened to notice that the left rear rotor was severely worn and recommended I replace it. I ordered the parts from Rock Auto, and after they arrived, Tom helped me change the brake pads and rotors, and replace the front bearings and seals.
Below is a picture of why everyone should check their brakes periodically, even if they feel like they are working fine… The inside pad on my left rear brake was completely worn down to metal, and had worn the rotor down to beyond what could be safely turned down.
Usually the most noticeable tell for metal on metal is a low scraping/grinding noise during braking. Damage usually happens quickly once that low tone starts.
The most badly worn rotor I have ever personally witnessed was on a 1986 Chevrolet Camaro, being driven by a fellow auto repair worker.
He’d been talking about fixing it for weeks, and finally pulled into the lot one day with ‘a leaking caliper’ being the final straw. We pulled it apart over lunch to find…
The rotor (vented) had worn completely away on 1 side, so the rotor fins were now the rotor braking surface.
This amazed me, but not as much as our next discovery: the PAD was completely gone, and the caliper piston had become the wear surface! It had gotten cocked in the bore, probably the first time it hit a vane, and was now worn at a weird angle, whilst leaking brake fluid. I have no idea how he made it to work without plowing into someone!
And for what it’s worth, most modern passenger vehicle rotors aren’t capable of, nor worth the bother to try, being turned.
Classics might be a different tale, but with anything made after 1976, roughly, it’s not really worth your time trying to get them turned.
Usually there are TONS of other warning signs, but with cars becoming more and more coffin-like in their sound deadening, it’s getting harder and harder to know. Most cars made in the current century have electronic warning mechanisms (usually a wear sensor on at least 1 pad and a light on the dash, or similar), but they cannot be relied upon. Folks who are aware, should be checking them at every oil change, every other, or at least once a year (at the VERY most, every OTHER year when the brake fluid is flushed…you ARE doing that, right? ) With any luck, if you are “unaware” or “disinterested”, hopefully you have a shop who is aware and/or interested helping you out; they should be doing the brake check outlined presently…
I’ve seen the exposed vanes in a rotor too - at the Lackland Air Force Base garage - a guy brought in a car he “just bought” with a “noise” - that rotor was on display for quite some time.
Most (again - not all) brake pad depth can be casually observed through alloy wheels without removing the wheel on many of today’s cars (current century as Jast says).
Stan was up at my place of work giving my boss some computer help when he asked me if I could tell if his van had 2 or 4 wheel disc without taking off a wheel - no problem - I looked under the rear from the passenger side and could see the left rotor wear - not good at all - and yes it has 4 wheel disc brakes (made the rear brakes much easier to service)
) With any luck, if you are “unaware” or “disinterested”, hopefully you have a shop who is aware and/or interested helping you out; they should be doing the brake check outlined presently…