Hi guys,

My brakes had been grinding for a while. The harder I pressed the more the grind was. It is not loud, but it is felt through the pedal.

Anyway, today I put new rotors and pads on assuming/hoping the issue would be resolved (the old ones only had a few mm of material left) but the grinding is now even worse.

What could this be?

The old pads were evenly worn, except on one side on pad had a bit more material left (about 3mm vs 2mm). I did not lubricate the pins, but they moved in/out without restriction

Did you do front and rear?

No I just did front, the rear rotor and pads were good by the way they looked.
Also it seems like the grinding is coming from the front left, but it is difficult to say if it really is just the left or whether the acoustics of the car make it seem like that.
The grinding noise isn't too loud so it is hard to tell. It is felt through the pedal though and the car itself

'Grinding' suggests you should will have shiny marks somewhere. Check the inside of the front left wheel rim. I cant remember the exact circumstances but my caliper, or a bolt, or something or other, was scraping the inside of my rim a few years ago,

No there are no marks.
Maybe I am not describing it correctly, basically I feel the brakes when I press the pedal, ie, it isn't smooth like it should be and there is a grinding type noise.

The old pads and rotors (though worn) looked fine, no uneven marks on the rotors or anything

No there are no marks.
Maybe I am not describing it correctly, basically I feel the brakes when I press the pedal, ie, it isn't smooth like it should be and there is a grinding type noise.

The old pads and rotors (thought worn) looked fine, no uneven marks on the rotors or anything

Looked for grind marks on the splash shields behind the rotors though?
They bend easily and touch the rotor, once you locate where it is happening, it is easy to fix.
Try jacking up one wheel at a time and rotate slowly by hand, you can hear and feel the roughness if that is the problem.

But this grinding only happen when I press the brakes. The harder I press, the louder and more pronounced the grind is.

But this grinding only happen when I press the brakes. The harder I press, the louder and more pronounced the grind is.

So? When you brake, play in any part of the wheel bearings & front suspension changes due to weight transfer and the change in drive. If your car is lowered, have you checked the drive shafts aren't touching any part of thr body work? Slim chance, but something is grinding and if you can hear/feel it, it should be leaving some tell tale marks somewhere. A thorough visual inspection is called for, not just looking at the rotors/callipers.

The car has completely stock suspension though.
I did inspect everything and nothing could be found. The old pads/rotors also had no sign of anything going wrong.

Could it be either of the below:
1. The rotors still have the cross hatch pattern on them since they are new, could this be causing the grind? Oddly enough these pads/rotors have zero noise when barely moving (most cars make noise at these near stationary speeds)
2. Could only 1 pad be applying pressure? ie, the floating pins being stuck somehow?

I don't want to start spending huge amounts of cash replacing things like bearings, rebuilding calipers etc

I would re-check your bearings. jack up the car/front/rear etc and try moving the wheel in the 12 and 6 positions as well as 9 and 3. With a big enough movement force but not big enough to turn the steering rack. You can either check for obvious play this way or get someone to watch you do it etc.

From my experience with wheel bearings, much grinding is to be had there... if yours is like mine your wheel play will be immediately obvious.

I did inspect everything and nothing could be found.


Better have another look, or get someone else to eyeball the car with the wheels off.

None of the things you suggest can cause a grinding noise or vibration you can feel through the pedal.

(I did once get a grinding noise from a front tyre that had water damage - water penetrated into a tyre and rusted the steel belts.)

Check the inside of the front rims to see if you have any grinding marks there. Seeing the problem was there with the old pads/rotors and is still there with the new stuff, you have some detective work to do.

Also check the rear, including handbrake shoes, if you haven't already.

I looked at the rear (wheels off, brakes left on) and nothing looked out of the ordinary. Rotors are in good shape, pads still have a decent amount of material.
It "feels" like it is coming from the front.

I will check for wheel movement, and I will grease up the pins ( I didn't do this).
Can the wheel bearings be worn out and causing grinding without any movement when testing them?

I looked at the rear (wheels off, brakes left on) and nothing looked out of the ordinary. Rotors are in good shape, pads still have a decent amount of material.
It "feels" like it is coming from the front.

I will check for wheel movement, and I will grease up the pins ( I didn't do this).
Can the wheel bearings be worn out and causing grinding without any movement when testing them?

yep, i dont have one with a super grinding noise on video but please observe 2 of my personal videos on stuffed bearings.
i haev replaced 12 bearings on a few of my cars already and have 4 waiting (spare magna ones to replace my on car ones). they are screwed and may grind but too late to go out and check....
note the mazda video i took the wheel off and was just before i pressed the bearing off and put new one in, but that is quite some play in there was grinding bad (started on just braking). do the tests with the wheels on.


https://www.youtube.com/watch?v=hoJVKx-9JJA


https://www.youtube.com/watch?v=JJ8NU1aDYQY

Mario

You say the rears looks ok, though are you assuming the inside is good because the outside is or have you actually checked them? The outside wear is usually a decent guide, but they can also seriously mislead. If you havent already, you should physically check the inside.

I didn't want to remove the rear pads as I don't have one of those tools that makes the caliper go back in.
The rear rotors look in great shape. Little wear, smooth surface. Pads seem to have at least half material.
Also seeing as the grinding got worse after the front brake installation, and it feels like it is coming from the front, then I assume it is a safe judgement call?

Pedders did a 28 point check and did not mention the wheel bearings, but I will check them over the next weekend, as well as check the calipers and rotors again + lube the slide pins

Hi guys,

My brakes had been grinding for a while. The harder I pressed the more the grind was. It is not loud, but it is felt through the pedal.

Anyway, today I put new rotors and pads on assuming/hoping the issue would be resolved (the old ones only had a few mm of material left) but the grinding is now even worse.

What could this be?

The old pads were evenly worn, except on one side on pad had a bit more material left (about 3mm vs 2mm). I did not lubricate the pins, but they moved in/out without restriction

When braking and you feel the grinding IN A SAFE AREA swerve left to right make sure your swerve is enough to transfer the weight as much as possible of each wheel if the noise goes when swerving /cornering to the right left bearing vis a versa worth a shot

yep, i dont have one with a super grinding noise on video but please observe 2 of my personal videos on stuffed bearings.
i haev replaced 12 bearings on a few of my cars already and have 4 waiting (spare magna ones to replace my on car ones). they are screwed and may grind but too late to go out and check....
note the mazda video i took the wheel off and was just before i pressed the bearing off and put new one in, but that is quite some play in there was grinding bad (started on just braking). do the tests with the wheels on.


https://www.youtube.com/watch?v=hoJVKx-9JJA


https://www.youtube.com/watch?v=JJ8NU1aDYQY

Mario

100% agree check bearings I will add the pajero has a bad front bearing no noise off the ground turning the wheel and no play but noisy when driving doing the corner left and right identified it straight away saw how to on youtube "chris fix" lot of good vids for a while I thought it was a bearing in the box or worse

Ok guys, so I lifted the car up again and had a look.
Everything seemed ok, bearings seemed fine with no play at all.

The pins did feel pretty stuck, and when I removed them there was no grease, just gunk.
I cleaned them up, greased them, and refitted everything.

Brakes are much smoother now, but still they grind a tiny bit. Seems abnormal.
The harder I press, the more they grind. Only at speeds over about 40-50km/h.

What could it be?

My money is on a warped rotor.Get it machined and see how it goes.

The rotors and pads are both new

I had the same problem, my pins slid in and out perfectly, however there was some sideways movement in them.
Two solutions :-
1) Replace all caliper pins pretty cheap option, which is what I did, and now no grinding noise at all
2) Sometimes repacking the slots/holes that the pins go into with fresh grease helps, but this is only a short term solution, best option is (1).
Hope this helps

Are these pins available new from Mitsubishi?

Also, can you check for this sideways movement? ie, by trying to move the caliper or something?