Brake Rotors

200 Pontiac vibe with 225,000 miles.

The brakes are making a grinding sound. I am assuming they need to be replaced. When I take them in they will probably say I need to have the rotors replaced (they never seem to be able to turn them these days). If I tell them to just replace the pads (in deference to the miles on this car) does anything bad happen. Is this a safety issue, or an aesthetic one?

Well, if your rotors are bad then they need replaced. If they simply replace the pads, and your brakes fail as a result of bad rotors, they could be held liable.

What is up with that? Whenever the dealership tells me I need new brakes, I ALWAYS need new rotors. ALWAYS. They can never been turned. If you go to Autozone and buy a brand new rotor and hand it to the Ford dealer and ask them to turn it, they will look at it, frown, and say that it is too worn down to cut. You need a new one. Until 15 years ago, I had never even HEARD of replacing rotors. You turned them (or “cut” them as the old guys called it).

Last time, my truck had 36k miles on it and it was the first brake pad change. Need new brakes and rotors. Bullshit. I pulled the tires myself and they didn’t even need cut. Two and half years later still doing fine.

Local mechanics always turn them, though. I think I see a pattern…

Well, that was my initial thought, but is it correct? Generally the rotors become scored and noisy. The question is whether this makes them less effective? If not, I am not going to spend the money on them.

Since my rant is over, it probably will depend on how bad the rotors really are. If they are truly shot, they will just chew up your new pads. This is why you need a trusted mechanic.

Fortunately, I have a mechanic that I trust. Let’s say he thinks the brakes will continue to grind because the rotors are slightly scored, and that the brake pads will then wear out more quickly. He will honestly recommend turning or replacing. My thought is that I can live with the noise, and the pads will still probably outlive the car (I drive a lot but most is limited access roads and I don’t brake that often).

Then have him turn them.

If that’s not an option for some reason, then I would still be wary. A grinding sound is never good, especially for an item like brakes. I wouldn’t want that at all.

Now, will you have a catastrophic failure causing a crash? Probably not, but you could have a lock up that destroys the calipers and what not, making rotors cheap by comparison.

I would beg and plead to get the rotors turned, but if he won’t then bite the bullet and get new ones.

The pads will wear faster, and the brakes might not have the same braking power. Rotors are so cheap these days that it costs more to turn them than to replace them.

I do my own brakes and constantly put pads on shitty rotors when the car has high mileage and I don’t care about pristine conditions. Maybe Gary or Rick will find this and provide a professional opinion, but it’s your car and if you tell the mechanic you don’t care about the rotor condition, it’s your call.

The stopping won’t be as even, and the bad rotors will chew through the new brake pads very quickly. I did it on an old truck once, when I was short for cash. I could afford the 15 bucks for brake pads but not the 100 bucks for a new rotor. So I just slapped on new pads and six months later replaced both the pads and the rotor. Because of the bad rotor, the pads were already shot after only six months.

Note that I replaced the pads myself. A shop typically guarantees their work and they might refuse to just change the pads, and might even refuse to turn the rotors if they don’t think they can get guaranteed results from them.

Some of it is probably lawyer-type CYA. If they turn the rotors and the rotors warp, and the brakes do something funky like grab as a result of it and cause an accident, they could be held liable.

I suspect that some of it is just them gouging you for profit.

To be fair, though, a lot of it is just that they make rotors much smaller and thinner these days, just as they make everything else smaller and thinner to cut down on weight. Rotors a couple of decades ago were significantly thicker and heavier and could usually be turned a few times before they completely wore out. The newer, smaller, and tighter fitting parts don’t allow as much of that these days.

once they start to “grind” during use, you’ve worn away all of the friction material on one or more pads and the rotors are now trashed. Gone. Kaput. You will replace them.

ETA: why did you let it get that bad in the first place?

It happened quite suddenly. I was away for a week and when I got back and drove the car for the first time it initially felt like the breaks were on, then I heard a quiet “pop” and then when I used the brakes I heard the grinding sound. I got new tires about 6 weeks ago and they said nothing about the brakes. I figured they must still be good. I can’t tell by looking myself, and would never consider taking the car in just to have an opinion on brakes that are behaving.

Man that is one freakishly old car.

how many miles since they were last done?

Brakes convert motion to heat. The rotor heats up and then cools when finished braking. The more beef in the rotor, the more heat it can absorb without over heating your brake linings. I think they have cheapened them coming from the factory only thick to last about one set of pads. Run them anyhow? 2 problems. Reduced braking capacity. Of course if you don’t drive like an idiot, you may get away with less. Also, the caliper piston must extend out further to push the pads further.

I do all my own work and skimp on replacing rotors. It has worked for me.

Really really old car. Ummm, maybe 2003 would be closer to the truth. I have no recollection as to when this was last done. However, I drive around 35,000 per year and don’t have to brake very often, so they should last a freakishly long time.

and you never once thought to have them checked? Even as part of an oil change or other service?

Not at all. I always assume that they check the brakes when they change the tires. That is usually when I hear I need new brakes.

Blame cheap Chinese labor. Car parts are as big a market for them as electronics. Consequently they’ve gotten so inexpensive as to be cheaper than the labor that shops can charge to cut them.

Also, I know it’s hard to accept but rotors should always be cut when you replace the pads. They’re not cut merely to remove any grooves from pad rivets, they’re cut to ‘roughen’ up their surface after being polished perfectly smooth for thousands of miles. The brakes will work much better this way.

If a dealer rejected brand new AutoZone rotors then they’re ripping you off. Not only are new rotors obviously going to be thick enough their surfaces come already machined with the proper roughness to be used right away. More likely it’s because repair shops simply don’t like customers bringing their own parts. I don’t blame them for that. You don’t bring your own eggs to restaurant and say “over-easy please”…

The grinding this is what disturbs me. That’s metal on metal. You are eating into those rotors and may have damaged them already.

I know that Pontiac’s are a pain in the ass (not sure about brakes, but other things), but I posted in another thread about brake replacement. It is pitifully easy. If you can operate a jack and a ratchet, you can replace pads and rotors (at least on my Ford F-150). My brother-in-law showed me how to do it and I am still kicking myself in the nuts for letting garages charge me hundreds of dollars for it. Never again.

No, that didn’t happen. That was smart ass hyperbole on my part.