Nearly New Rotors and Brake Pulsation

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Last summer, I put new front rotors and pads on my MKZ. I used NAPA premium pads and rotors.

I call these "nearly new" because of how little I've driven the car in the past year between my wife doing most of the long distance driving and my going into the office two days a week if that. My notes indicate a bit over 5K miles. No one but me has touched the wheels/lug nuts since I put them on, and my usual install process, all in a star pattern, is snug with a 12" ratchet, torque in a star to 50 ft-lbs, and torque again to 100 ft-lbs.

I don't know how I could possibly had overheated these or done anything that would cause pad transfer. Most of my driving is low speed around-town or open road 70mph. It's flat enough around here that I'm not on them that much to keep speed in check, and my commute to work has little enough traffic around that sudden or hard stops are a rare event.

Still, though, I've developed a NASTY vibration/pulsation. I'm putting it on the front brakes because I feel it in the steering wheel when I'm on the brakes, and it's there even with fairly light braking.

I'm GUESSING I've developed a rotor issue, but again I don't see that I've done anything that would have caused it.

None the less, I'm wondering about remedies. I hate to dump these pads with this little mileage on them, but also I wouldn't want to do anything to the rotors without putting new pads with them.

As I see it, I have two basic options:

1. Turn the rotors, which I can have done locally for $10 each. My worry on that is that there's some sort of defect in the rotors that caused uneven wear and vibration in the first place, and turning would just hide it for a few more miles

2. Replace

Looking at options, I can get the same NAPA Premiums for $46, on up to $66 for Ultra Premium(and a "Proformer" between the two). They also have a "Freemont" brand rotor for $125(ouch) and say "Freemont is an OEM manufacturer"(although I don't know if that means OEM to the car...the phrasing makes me think not).

I can also get Motorcraft for $71.65 at the dealer.

Part of me is tempted to try turning since it's 1/5 the cost of even the least expensive option, and I know true rotors aren't necessarily guaranteed out of the box.

Still, though, if I'm going to fix this I want to not deal with this again for a while.

Any suggestions first of all if I could be overlooking something that points to it not being a brake/rotor issue, and second what you all would do in my situation.
 
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Pull the pads an see if there are wearing unevenly, top to bottom. I once had an Accord that pulsated badly due to uneven pad wear.

I would check for rotor runout in a couple different spots in the rotor.
The hub was rust free when you installed the rotors, right?

Good luck.
 
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I have experienced the same issue (pulsation within 5-10K miles) of a brake job over the last few months. Both instances were with the same brand of aftermarket pads, but was the company's copper-free formula. I think some of these new formulas are not very good and are either leaving excessive pad deposits or wear rotors unevenly. In both situations, the rotor runout was measured prior to install and was <.001".

I think you need to try a new pair of rotors and possibly some dealer pads.
 

bunnspecial

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Thanks guys.

I'll try a bed-in as a first stop since I guess it can't hurt anything. The biggest issue is going to be finding a stretch of road where I can do it safely.

Otherwise, I'll just bite the bullet and grab Motorcaft pads+rotors.

BTW, @The Critic when you mean the "same brand" do you mean NAPA premium, or do you mean both of yours happened with the same(other) brand of pad?
 
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Same issue with our '18 Hyundai . Very bad when braking at the bottom of a hill . Pedal is soft as well . These are the factory installed pads and rotors . I think there's over 25,000 miles on the car . Wonder if they use cheap parts .
 
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I have experienced the same issue (pulsation within 5-10K miles) of a brake job over the last few months. Both instances were with the same brand of aftermarket pads, but was the company's copper-free formula. I think some of these new formulas are not very good and are either leaving excessive pad deposits or wear rotors unevenly. In both situations, the rotor runout was measured prior to install and was <.001".

I think you need to try a new pair of rotors and possibly some dealer pads.
Copper in the pad compound prevents rotor corrosion. Rotors corrode much easier/faster without it.

OP probably just has corrosion where the pads sat for an extended period. If the corrosion is not too bad, they can be machined.
 

bunnspecial

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So, I did bed the brakes and it's improved. It's still there at ~70mph, but not as bad. I can feel it at lower around town speeds if I pay attention, but before it was definitely noticeable.

The plan next week is to throw Motorcraft pads and rotors on...

BTW, even though the mileage is low, the car really hasn't sat any appreciable amount of time. It's typically driven a couple of days a week, and I make sure to drive long enough to get it up to temp and so forth.
 

bunnspecial

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I'm wondering if the remaining pulsation I'm feeling is from the rears. It looks like I have a lot of pad residue built up on them.

IMG_0128.jpeg


The rears are somewhat older than the fronts. Maybe about 2 1/2 years ago, when I was driving a WHOLE lot more, I had a caliper stick and wear the right rear down to the metal backing. Needless to say I trashed the pads and rotors both-the caliper was fine after a clean and regrease of the sliding pins. I'd guess these have ~20K on them, but can look and say for sure.

Maybe I should do the rears first before tackling the fronts, or maybe just bite the bullet and do all of them.
 
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I've wondered how do you really burnish rear brakes.... Most recent situation was I replaced front/rear pads/rotors on daughter's Civic and used Raybestos Element3/EHT coated rotors. After doing the work, took it out to burnish everything and with coated rotors, it's really easy to see how you're progressing because the pads burn/clean off the coating in the contact area. Fronts looked great - a good, distinct inner and outer circle showing where the pad contacts. On the rear though, while there was a fairly distinct circle for the bottom of the pads, it kinda faded or had a gradient look towards the top. It eventually cleaned up over time though.
 

bunnspecial

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If your wife drives like most wives drive, i think it’s safe to assume the culprit has been identified 🧐

Well, she swears by her Jeep-a 2018 Compass-and I swear at it any time something goes wrong on it :) .

She doesn't particularly like driving my car because "it sits too low." An MKZ isn't exactly a speed demon(the LS I had before it could move pretty decent with its peppy little AJ-V8...I miss that car) but a V6 in a sedan can move things along a lot faster than a 4 cylinder in a CUV. My primary/dailies have always been V6 or V8 Sedans, and my secondary cars have mostly been 4 cylinders(the Ranger and the MG stand out), which I know is opposite how people normally do it, but I like the simplicity of NA engines and like how 6 and 8 cylinder engines drive. Meanwhile, she's never owned anything but little NA 4 cylinders tuned for economy(Cavalier, Camry, and now on her second Compass) and I think that my car scares her because it moves a bit more than she's use to.
 
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Sorry, I should have been more clear. I experienced the same issue, but with Centric pads.
I've stopped using Centric for now. Maybe I'll try them again in the future but I am having a bad stretch of luck with them.
Mine were the Posi-Quiet Ceramic and 120 Rotors. Next were the C-Tek matched pad/rotor kit from RA. Not impressed with Centric.
 
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I'm wondering if the remaining pulsation I'm feeling is from the rears. It looks like I have a lot of pad residue built up on them.
Why would you even keep those junky rotors? The grooves in them will damage the new pads.
Any new rotor is fine, maybe get one with a coated hat (rust proof). A rotor isn't something that can be screwed up with modern tool/machines, even on Chinese brands.
The pads, on the other hand, are a different animal. They are to blame for 99% of the "pulsation in brake pedal" issues, but people keep blaming the "warped rotors", because they don't understand the process.

The brake pads deposit a layer of braking material on the discs.
That layer needs to be uniform and thermally stable. That's why the quality of pads and initial bedding of the pads is extremely important!
Even "good" pads, if they are not bedded per manufacturer instructions, will go "bad". It isn't just a "slap and go" type of deal.

Any in-uniformity on the deposited layer will only accentuate with every braking action (material will be deposited more in places where there is already more material, because that's where the heat will be generated). And so, the pulsation will appear after a few hundred miles driven (in the city), with about a thousand braking actions.
Staying at stop light, with foot hard pressed on fresh and not bedded pads, will just print those pads on the hot steel rotors. That's the main source of pulsation.

Get quality pads, from reputable manufacturers, even if they cost a bit more. Or even get OEM pads, usually they are good. I gave up on using "store brand" pads, they didn't work for me.
When I change my pads I also order new rotors. They are so cheap and I am doing this every 10 years, so why use rusted and f-t up rotors? They will just damage the new pads!
 
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bunnspecial

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Get quality pads, from reputable manufacturers, even if they cost a bit more. Or even get OEM pads, usually they are good. I gave up on using "store brand" pads, they didn't work for me.
When I change my pads I also order new rotors. They are so cheap and I am doing this every 10 years, so why use rusted and f-t up rotors? They will just damage the new pads!

Every brake job so far on this car has had new rotors. The coming one will get them also, and yes I'm going OEM.

I was under the apparently mistaken impression that NAPA Premium brake parts were good stuff.

I use to trust NAPA branded stuff implicitly, especially in their mid to higher range products. It looks like maybe that's not a safe thing to do anymore.

BTW, yes, I always make sure the hub is in good shape before dropping a rotor on. In the past, for lack of better tools, I've generally used a wire brush on a drill combined with sanding by hand. . I at least have some pneumatic tools now that make quick work of rust with knotted brushes, so will use those.
 
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I used wire brushes before on hubs, combined with brake cleaner fluid.

I too feel that new rotors once every 5-7 years is not the end of the world.
 
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