Rotors are scored but pads aren't worn down...causes? Do I need new rotors?

[996GT2]

So just when I thought I was done with all the maintenance on my car for a good while (just did the valve adjustment), another issue pops up. Car is a 03 Accord EX with 133K.

The rear brake pads were replaced last summer, and the rotors were refurfaced by the dealership. However, today, I notice this on the left rear rotor:

The score marks go all the way around the rotor. The other 3 rotors look fine. What's interesting is that my brake pads still have life in them. I also do not notice any noises when braking.

What could cause rotors to be scored before the pads are worn down? Should I replace my rotors or keep driving with them since there aren't any symptoms yet?

 

[crashtech]

Hard to tell from pics, but it looks like foreign material lodged in the pad/rotor interface. I would drive it but increase the rate of checking, based on the fact that rotors are so cheap it's better to just replace them than turn them anyway.

If OCD wins out, removing the caliper and inspecting the pad surface becomes mandatory.

 

[MongGrel]

Looks like something lodging in the pads to me, yeah.

Bit odd looking to me, something going on the pads grinding on the disks, but that's obvious I guess.

 

[Jimzz]

Do you know what brand pads it is? I have seen grooves like that from a bad brake pad mix before. Like a larger piece of metal got into the pad mix.

As said take the brakes off and inspect the pad and caliper. Take some pictures and post as well.

 

[JulesMaximus]

How deep are the groves? Any strange feeling in the brakes when applied? If it's just cosmetic I wouldn't even worry about it until your next brake job.

 

[996GT2]

Do you know what brand pads it is? I have seen grooves like that from a bad brake pad mix before. Like a larger piece of metal got into the pad mix.

As said take the brakes off and inspect the pad and caliper. Take some pictures and post as well.

Last time the brakes were done (last summer), it was done at the Honda dealership. So I'm going to assume that genuine Honda pads were used. They didn't replace the rotors at that time, but did resurface them.

How deep are the groves? Any strange feeling in the brakes when applied? If it's just cosmetic I wouldn't even worry about it until your next brake job.

The grooves aren't too deep but they can be felt when running a finger across the rotors. No noise and nothing too strange when applying the brakes. I did notice that the left rear pad was worn much more than the right rear pad, even though both were replaced at the same time last summer.



So what would be a good plan to go with? Keep driving it until the rear pads get worn down and need replacement, and then replace both pads and rotors?

 

[phucheneh]

I've seen much worse grooving before, and it's generally no cause for alarm.

However, in such cases, the grooves are small and have the same shiny look as the rest of the rotor. What you've got going on looks a lot more like when the rotor is hitting the caliper bracket. The most typical cause is a bad hub bearing, which is allowing the hub flange to move around and hit the stationary bracket. I've also seen shoddy hub bearing jobs manage to hold together, only to be exposed when someone puts new rotors on the car- you can have (for example) a hub flange is not pressed all the way into the bearing, and it doesn't cause an obvious issue until a new (thicker) rotor causes interference.

Or the bracket can just be loose from the spindle. But that usually results in knocking, clunking, or some such worrisome noise.

 

[996GT2]

I've seen much worse grooving before, and it's generally no cause for alarm.

However, in such cases, the grooves are small and have the same shiny look as the rest of the rotor. What you've got going on looks a lot more like when the rotor is hitting the caliper bracket. The most typical cause is a bad hub bearing, which is allowing the hub flange to move around and hit the stationary bracket. I've also seen shoddy hub bearing jobs manage to hold together, only to be exposed when someone puts new rotors on the car- you can have (for example) a hub flange is not pressed all the way into the bearing, and it doesn't cause an obvious issue until a new (thicker) rotor causes interference.

Or the bracket can just be loose from the spindle. But that usually results in knocking, clunking, or some such worrisome noise.

Wouldn't a bad wheel bearing lead to noises? So far I haven't heard any abnormal noises when driving or using the breaks, save for the slight disc break squeal that happens once in a while (but I've experienced that on all cars).

 

[phucheneh]

I just noticed those were rear brakes. Also your car is quite rusty. Rusty cars and sticking rear calipers tend to go hand in hand.

Are you sure you've got pad left? You may have a stuck caliper pin that is resulting in some strange, uneven pad wear. Look through the hole in the caliper, where you can see the very outer edge of both pads.

If those marks on the rotor are not from just getting to the end of the pad material, they could also be from part of the pad not making good contact with the rotor- i.e. the rotor gets 'cleaned' every time you stop, but somehow the pad has very uneven pressure. Again, probably due to sticking caliper pins (or just the pad being stuck in the slides).

 

[996GT2]

I just noticed those were rear brakes. Also your car is quite rusty. Rusty cars and sticking rear calipers tend to go hand in hand.

Are you sure you've got pad left? You may have a stuck caliper pin that is resulting in some strange, uneven pad wear. Look through the hole in the caliper, where you can see the very outer edge of both pads.

If those marks on the rotor are not from just getting to the end of the pad material, they could also be from part of the pad not making good contact with the rotor- i.e. the rotor gets 'cleaned' every time you stop, but somehow the pad has very uneven pressure. Again, probably due to sticking caliper pins (or just the pad being stuck in the slides).

Yes, the hubs are rusty, but I don't think there is a way around it, since the car has been garaged most of its life. The rest of the car is quite free from rust.

Pad wear looks normal from all 4 sides on the left rear brake.

 

[phucheneh]

Wouldn't a bad wheel bearing lead to noises? So far I haven't heard any abnormal noises when driving or using the breaks, save for the slight disc break squeal that happens once in a while (but I've experienced that on all cars).

Nope, not always. You generally get noise when the actual balls or rollers have worn into odd shapes (they're no longer round). But sometimes the bearing still rolls smoothly, but the races are worn and some extra clearance has been created. This results in play that can be felt by raising the car and shaking the wheel back and forth. Same way you'd check for bad tie rods, except instead of gripping the wheel at 3 and 9, 12 and 6 will usually be the easiest way to feel it.

 

[crashtech]

Pretty hard to diagnose in low res 2D, but I was presuming these anomalies are not deep, but more like marring instead of gouging. If it is apparent that something is cutting deeply into the surface of the rotor, it needs to be looked at very soon.

 

[996GT2]

Pretty hard to diagnose in low res 2D, but I was presuming these anomalies are not deep, but more like marring instead of gouging. If it is apparent that something is cutting deeply into the surface of the rotor, it needs to be looked at very soon.

The grooves are not deep at all. They can just barely be felt by running a finger across the rotor surface. I would estimate that they are <1mm deep for sure.

 

[crashtech]

If cost is no object, go get it fixed. But it sounds like your vehicle is asymptomatic at this time, so my original advice of keeping an eye on it stands. Someone who is proficient could quickly remove the caliper bracket and determine if there is foreign material involved or if it is indeed some kind of physical contact issue. I doubt the latter is the case because it's very likely there'd be noise. I also think that a bearing issue is unlikely, but possible.

 

[996GT2]

If cost is no object, go get it fixed. But it sounds like your vehicle is asymptomatic at this time, so my original advice of keeping an eye on it stands. Someone who is proficient could quickly remove the caliper bracket and determine if there is foreign material involved or if it is indeed some kind of physical contact issue. I doubt the latter is the case because it's very likely there'd be noise. I also think that a bearing issue is unlikely, but possible.

I'm due for an oil change in about 3 weeks, so I'll have my mechanic look it over then. If it starts making noise before then, I'll remove the pad and inspect it for damage.

 

[BassBomb]

Lots of rear caliper issues known for our car bud. Get the sliders and pins and all the mechanism checked out. They could be seized or in need of service.

Happened to me, I replaced the calipers but I think I only needed to get it properly serviced and the pins replaced.

I got the same "its just pad material" explanation from others. Your grooves are a lot worse than mine though.

 

[JulesMaximus]

Last time the brakes were done (last summer), it was done at the Honda dealership. So I'm going to assume that genuine Honda pads were used. They didn't replace the rotors at that time, but did resurface them.



The grooves aren't too deep but they can be felt when running a finger across the rotors. No noise and nothing too strange when applying the brakes. I did notice that the left rear pad was worn much more than the right rear pad, even though both were replaced at the same time last summer.



So what would be a good plan to go with? Keep driving it until the rear pads get worn down and need replacement, and then replace both pads and rotors?

Okay, that is more worrisome and might be indicative of a sticking caliper or some sort of binding with the pins. I would have it checked next time you take it in for service.

 

[996GT2]

I jacked up the rear wheel and tried to spin it. The left side does not spin freely, so I suspected a sticking caliper. Took it to the dealership for an inspection and indeed this was the case. They wanted $525 to replace just that caliper and the pads, not even the rotor! I got out of there fast and called up my mechanic, who quoted a very fair ~$120 ish in labor to replace both rear rotors, pads, and that caliper. I'll probably go with Honda OEM pads, and since rotors aren't super expensive and the old rotors have been on there for 100K+ miles, I am going to replace those as well.

Any recommendations for good OEM-style rotors? I'm thinking EBC UR series rotors, which add up to around $170 for a set of 4 from Amazon.

Also, the Honda OEM caliper is $130 from an online Honda dealer. Would it be best to go with the genuine Honda part, or are there any third party calipers that are comparable in quality?

 

[mirageracerx]

i have gone aftermarket and never looked back. oem parts are of a certain quality, but worse quality parts typically dont sell too well on the interwebs. i would suggest looking up the parts on rock auto and going from there.

 

[Jimzz]

i have gone aftermarket and never looked back. oem parts are of a certain quality, but worse quality parts typically dont sell too well on the interwebs. i would suggest looking up the parts on rock auto and going from there.

THIS

You think Honda has a brake pad and caliper factory? You're just paying extra for the name on the box. The Gold and Platinum pads from advance work well for the Hondas I have used them on.

 

[phucheneh]

THIS

You think Honda has a brake pad and caliper factory? You're just paying extra for the name on the box. The Gold and Platinum pads from advance work well for the Hondas I have used them on.

Honda doesn't have a caliper factory, but neither do the companies selling calipers to the parts stores. They have a facility for 'remanufacturing.' So yeah, there is a difference.

...but not enough for me to care. I've used tons of remanned calipers without incident. There's a reason people used to just rebuild the things themselves- it's not exactly a complex procedure. Remans are going to have a cleaned up housing, new piston, new seal, and new dust boot. The piston and the seal are the big things; if you truly get a sticking caliper (not just stuck pins), the problem lies in the interaction between the piston and the seal. The calipers get full of gunk, or the piston gets rusty and pitted, or the seal gets swollen or torn.

For pads, look for Akebonos. Probably $50 a set, and about the best you'll get. Akebono may even make the OEM pads for Honda.

 

[silicon]

I jacked up the rear wheel and tried to spin it. The left side does not spin freely, so I suspected a sticking caliper. Took it to the dealership for an inspection and indeed this was the case. They wanted $525 to replace just that caliper and the pads, not even the rotor! I got out of there fast and called up my mechanic, who quoted a very fair ~$120 ish in labor to replace both rear rotors, pads, and that caliper. I'll probably go with Honda OEM pads, and since rotors aren't super expensive and the old rotors have been on there for 100K+ miles, I am going to replace those as well.

Any recommendations for good OEM-style rotors? I'm thinking EBC UR series rotors, which add up to around $170 for a set of 4 from Amazon.

Also, the Honda OEM caliper is $130 from an online Honda dealer. Would it be best to go with the genuine Honda part, or are there any third party calipers that are comparable in quality?

OEM is without a doubt the best quality. But aftermarket parts are very good also...ask a lot of questions if you go the parts jobber for brake pads.

 

[silicon]

I jacked up the rear wheel and tried to spin it. The left side does not spin freely, so I suspected a sticking caliper. Took it to the dealership for an inspection and indeed this was the case. They wanted $525 to replace just that caliper and the pads, not even the rotor! I got out of there fast and called up my mechanic, who quoted a very fair ~$120 ish in labor to replace both rear rotors, pads, and that caliper. I'll probably go with Honda OEM pads, and since rotors aren't super expensive and the old rotors have been on there for 100K+ miles, I am going to replace those as well.

Any recommendations for good OEM-style rotors? I'm thinking EBC UR series rotors, which add up to around $170 for a set of 4 from Amazon.

Also, the Honda OEM caliper is $130 from an online Honda dealer. Would it be best to go with the genuine Honda part, or are there any third party calipers that are comparable in quality?

have you mechanic inspect the pins as i have heard that they may only need cleaning,,,no need to swap the caliper if this is the case.

 

[Jimzz]

OEM is without a doubt the best quality. But aftermarket parts are very good also...ask a lot of questions if you go the parts jobber for brake pads.

Based on what? As I said before, you think Honda or any other car maker has a brake pad factory?

 

[silicon]

Based on what? As I said before, you think Honda or any other car maker has a brake pad factory?

typically the factory will source parts that have to meet certain minimum specs. This is OEM and you are right, they do not have a factory themselves to make the parts. great variability in parts quality, even if you walk into a honda dealer and buy brake pads from the parts counter, these are of lower quality usually.