Vibration under braking fixed with new rotors but coming back

[M104]

Hi everyone, i had a severe vibration while braking at all speeds and new rotors completely fixed the issue. At the time i also used sand paper to make the surface of the pads rougher.

5000 km later the car starts shaking again, especially at high speeds. My front suspension is not in the best shape, it needs LCA bushings and a tie rod i think but as i said, the issue was 100% gone for a while.

 

[CharBaby]

Before installing the rotors, did you clean/wire wheel the hub mating surface?
I'm not sure on the "sanding of the pad surfaces"

 

[M104]

Yes, i made sure everything was spotless. I remember sanding the pads just a bit on a perfectly flat surface and something like 80 grit sand paper because i thought they looked slightly glazed.

 

[demarpaint]

Did you use a dial indicator when you installed them to check them? USING DIAL INDICATOR Sometimes they're out, and rotating them one lug nut forward or backwards resolves that issue. I doubt sanding the pads is going to do much of anything to be honest.

 

[M104]

Great advice. Could the worn LCA bushings amplify something that i wouldn't be able to feel otherwise? I'm tempted to replace them anyway as the cars is exhiting others symptoms: Shimmy at some speeds especially around 100 km/h, rough ride on bad roads and slow/vague steering response.

 

[benjamming]

What rotors & pads did you use?

 

[M104]

If memory serves, Bosch discs and Ferodo pads.

 

[shortyb]

Fix your suspension components. They may contribute to braking issue, but likely not. They DO contribute to poor handling response you describe and could be unsafe. Check runout and mating surfaces as @demarpaint describes to eliminate unevenness. I suspect the rotors and pads could be the issue and is quality centered (I see now you used Bosch rotors and Ferodo pads). Not a big fan of Ferodos, but in your location they may be better. Oh, and never use sandpaper to break glaze or "smooth" out the pads. It leaves carborundum particles in the pad material that can cause hot spots and grooving of the rotors. Use a glaze breaking stone or garnet paper if you must.

What vehicle is this on?

 

[ka9mnx]

Repair the front end. It's amplifying the problem.

Have the front rotors turned (trued). I had the same problem with new rotors. After having the rotors turned, the shaking went away.

 

[shortyb]

Repair the front end. It's amplifying the problem.

Have the front rotors turned (trued). I had the same problem with new rotors. After having the rotors turned, the shaking went away.

Turning, or resurfacing, or "skimming" rotors will get rid of uneven pad material deposits which can cause brake judder. But unless you change something you do, they will probably return. Soft pads are notorious for this and Ferodos in my experience have been very soft. Couple that with harder rotors and improper/no bed-in, always in abrasive mode while braking (light on the pedal for longer distances) or getting rotors hot and leaving pads against them at a stop etc. is a perfect storm for judder to return.

 

[demarpaint]

Did you use a dial indicator when you installed them to check them? USING DIAL INDICATOR Sometimes they're out, and rotating them one lug nut forward or backwards resolves that issue. I doubt sanding the pads is going to do much of anything to be honest.

The link was working when I posted it. Anyone interested just search: "using dial indicator to check rotor run out."

 

[D1dad]

I had a vibration similar. New rotors would be good for a bit then come back. Ball joints were newish, inner and outer tie rods replaced ,new shocks, bearings and mounts and still couldn’t chase it down. As a last ditch effort I replaced both front wheel bearings (it was all that was left) and boom…fixed. I was relieved yet PO’d. There was just enough play under load yet nothing that screamed wheel bearing. I think the wobble slowly warped the rotor. I just actually replaced a front right wheel bearing (first) on my 2021 due to a vibration. I suspected a wheel bearing after I hit a pothole big enough to swallow a Kia soul on I75. I did get the tires balanced before hand just to be safe.

 

[E150GT]

Did you use a torque wrench to set the lug nuts nice and even on the wheel ?

 

[Sequoiasoon]

Over the years many also had issues from unevenly torqued lug nuts contributing to that. I don't recall that but I do most of my own work and torque mine the same.

Many of my issues when that happened was as above with brakes nice and hot and then holding pedal down hard at a stop light. Pad material transfers and leaves the deposits. Some of them I was able to "fix" by redoing the bedding process of some hard 60mph-5mph slow downs followed by a longer cool off. If I have to stop while doing that I will crawl very slowly to the light probably in neutral and then use parking brake.

 

[D60]

I had a vibration similar. New rotors would be good for a bit then come back. Ball joints were newish, inner and outer tie rods replaced ,new shocks, bearings and mounts and still couldn’t chase it down. As a last ditch effort I replaced both front wheel bearings (it was all that was left) and boom…fixed. I was relieved yet PO’d. There was just enough play under load yet nothing that screamed wheel bearing. I think the wobble slowly warped the rotor. I just actually replaced a front right wheel bearing (first) on my 2021 due to a vibration. I suspected a wheel bearing after I hit a pothole big enough to swallow a Kia soul on I75. I did get the tires balanced before hand just to be safe.

This is an excellent point. I've always wondered how it just seems to work itself out with wheel bearing play ‐‐ esp on old school systems with individual races and bearings that you'd pack by hand. In those cases it's often impossible to eliminate all play, so the rotor can move around a bit relative to the caliper (which is, of course, fixed).

I could see where this could cause a vibe when braking, particularly on a newer vehicle with unit bearings where such play was never anticipated or considered.

That said, I would NOT fire the parts cannon and just replace the wheel bearings yet. Merely saying it may be a consideration.

 

[Mechanician]

It's not unheard of for rotors to need a cut after they become "seasoned." Your loose suspension parts are probably amplifying the minor distortion.
Should be done with an on the car machine, but since it was good when they were new, you may be fine with an off car trim.

 

[D1dad]

This is an excellent point. I've always wondered how it just seems to work itself out with wheel bearing play ‐‐ esp on old school systems with individual races and bearings that you'd pack by hand. In those cases it's often impossible to eliminate all play, so the rotor can move around a bit relative to the caliper (which is, of course, fixed).

I could see where this could cause a vibe when braking, particularly on a newer vehicle with unit bearings where such play was never anticipated or considered.

That said, I would NOT fire the parts cannon and just replace the wheel bearings yet. Merely saying it may be a consideration.

I agree on the parts thing. In my case, my car was well over 100k so front end parts were inevitable. I haven’t had a traditional growling bearing since my wife’s T&C mini van, yet have replaced several. Loose steering, pulling slightly, a hum that no one outside of myself could hear, vibration at only certain speeds. The one I just replaced was tighter than tight in the air and no noise spinning it. Nissan had just replaced the left under warranty, so rather than spending all day at the dealer, I ordered a bearing and did it myself. Problem solved and no more vibration @60 mph. Plus a bearing is so cheap and easy now days I’m half considering just doing it with my brake jobs so I don’t have to grind and brush my hubs in hopes that they’re perfect. I could do new pads, rotors and wheel bearings for half what a dealer would charge for brakes alone. Not that I’d go to a dealer. I know I’ve got one going on my 18 rogue. Slight hum and pulls slightly right, yet nothing that screams replace me. And the alignment is spot on. I’m considering Gsp. I’ve got two in my cart for $100.

 

[ka9mnx]

Turning, or resurfacing, or "skimming" rotors will get rid of uneven pad material deposits which can cause brake judder. But unless you change something you do, they will probably return. Soft pads are notorious for this and Ferodos in my experience have been very soft. Couple that with harder rotors and improper/no bed-in, always in abrasive mode while braking (light on the pedal for longer distances) or getting rotors hot and leaving pads against them at a stop etc. is a perfect storm for judder to return.

Two years and the problem has not returned. Pads are ceramic (ugh).

 

[CapitalTruck]

Repair the front end. It's amplifying the problem.

Have the front rotors turned (trued). I had the same problem with new rotors. After having the rotors turned, the shaking went away.

Its getting harder to do brakes in the driveway now because new rotors come warped out of the box. Drums too.

 

[eljefino]

Wife's HHR had a front end shake when braking, turns out it was the steering intermediate shaft. Absolutely fix your LCA bushings.