[Logicoeur]

Rotors don't bend or warp.

[AlmondJayRoM3]

Originally Posted by Logicoeur

Rotors don't bend or warp.

This. Bad runout maybe. Or as said in an earlier reply, improperly bedded brakes that cause inconsistent grab.

I’ve tracked plenty of cars and overheated brakes plenty of times and never had a warped rotor.

So rather than continuing to fire the parts cannon at your car, maybe a good diagnosis is in order and we’ll worth the money. You need to figure out why you keep burning through the same parts quickly. Go to a reputable mechanic. If you still don’t want to pay for a diagnosis do some stuff to try and figure out the problems. If it were me I would check for a stuck caliper piston or slide. Drive and see if one rotor or wheel is getting a lot hotter than the others.

[Billfitz]

Originally Posted by Logicoeur

Rotors don't bend or warp.

They don't bend, and technically don't warp. When they overheat it's uneven, resulting in high and low spots that cause pulsation. It's not really warped, but that's what it's usually called.

[HighlandPete]

Originally Posted by Danny35

I belive so , I can show you every single time when I bought them. I've tried every single brand. The brembo last more then the others. I didnt check every single time if they got bend in both sides , I've just did it today and find out that is the left side. So I guess it was all the time on the left side. I'll see tomorrow what the guy says, I already got the discs , pads and I might buy the calipers and the carriers as well , I'm already tired of doing them every single 3-4 weeks

You need to get to the 'real' issue, not keep replacing discs and pads.

What is exactly happening? Can't see it clearly spelled out in your posts.

Heat without braking hard? If so, and brake components are working fine at rest, I'd suggest the ABS system needs investigating.

[CJKaz]

A through inspection of all the rotating components with a dial indicator is in order:

1. Rotor off, runout of the hub. Possibly bent (unlikely).
2. Flatness (corrosion) of the hub mating surface to the back of the rotor.
3. Corrosion on the back mating face of the rotor.
4. Runout of the assembled rotor on the hub.

As mentioned, a stuck caliper can overheat the rotor. Check with an infrared heat gun, or surface thermometer after a gentle drive. A dragging caliper will also show up turning the wheels when wheels are off the ground (a little less scientific).

A stuck caliper slide pin can overheat one face of the rotor. Based on the number of times yours have been disassembled, this should have been found & corrected.

[Zheez]

I had a similar issue on my 2010 E90 and I never did get to the bottom of it.

I did over 60k miles on a set of discs/rotors and pads taking the car to about 140k before I started getting bad juddering when braking. It was noticeable at all speeds but most obvious at 60mph and over. I couldn't work out whether the vibration was coming from the front or rear but I suspected the rear which turned out to be wrong.

I changed the discs and pads and everything was fine, for a few weeks. I changed discs and pads again, but this time I did the rear first and it didn't fix the problem. Changed the fronts and it went away but again only for a few weeks. I then got my brake discs/rotors skimmed which made them look as good as new and they were verified to be completely flat. This fixed the problem, yet again only for a few weeks.

At this point it was obvious something else was up and that changing discs/rotors all the time was a waste of money so I unbolted both front calipers, pushed the pistons back in and refitted them with the same discs and pads and the problem went away again. It was fine until I got rid of the car (gearbox went) but I'm sure the vibration would have come back eventually.

This made me believe it was related to one of the front calipers. If I kept the car I would have then narrowed down which one it was and just replaced the caliper/calipers if needed, but I never got that far.

[BMWILUVU]

Originally Posted by Danny35

I belive so , I can show you every single time when I bought them. I've tried every single brand. The brembo last more then the others. I didnt check every single time if they got bend in both sides , I've just did it today and find out that is the left side. So I guess it was all the time on the left side. I'll see tomorrow what the guy says, I already got the discs , pads and I might buy the calipers and the carriers as well , I'm already tired of doing them every single 3-4 weeks

This is so rare that I can hardly believe it could be the caliper, hub, or wheel carrier being out of alignment possibly. Did you ever potholed the left side or curbed it badly?

[Danny35]

Originally Posted by BMWILUVU

This is so rare that I can hardly believe it could be the caliper, hub, or wheel carrier being out of alignment possibly. Did you ever potholed the left side or curbed it badly?

I've took some potholes with that side yes , I even change the left front tyre , but I don't know what cannit be. Anyway , I've change the discs pads , calipers and carrier calipers today , if this won't fix the issue I will kill myself!

[HarryTee]

"if this won't fix the issue..."
I wonder if there's any garage who could do the repair for you with a guarantee to look at it again until the problem is resolved (if their previous attempts don't resolve the issue). Try exploring this.

[Wires]

Originally Posted by Danny35

I've took some potholes with that side yes , I even change the left front tyre , but I don't know what cannit be. Anyway , I've change the discs pads , calipers and carrier calipers today , if this won't fix the issue I will kill myself!

Just sounds like you are perpetually tossing good money after bad but not actually looking for the true root cause of the problem.

[Billfitz]

Agreed. Search Einstein's definition of insanity.

[Wires]

Originally Posted by Billfitz

Agreed. Search Einstein's definition of insanity.

For reference:
“The definition of insanity is doing the same thing over and over again and expecting different results.”

[mmm-five]

Originally Posted by Wires

For reference:
“The definition of insanity is doing the same thing over and over again and expecting different results.”

Are we all insane in trying to get our cars to start first time after a long rest?

You try it first time...nothing.

You try it again...nothing.

You try it again...vroom away we go!

[casualDIYer]

Originally Posted by Logicoeur

Rotors don't bend or warp.

Agree. They’re cast iron monsters. While warping is unlikely they can crack, which is why I stay away from drilled. Slotted or blanks are fine but slotted can’t be refinished.

As for the OP, maybe I missed it but did you buy the car new or used? As a new car pads and rotors last quite a while if you’re not tracking it. I’ve seen 80,000 km / 4yr cars on the original set of pads and rotors. More than one set in 1 year is definitely not normal unless you are tracking the car. So, regular driving should mean years, not months of use, right?

All the tips given sound like all the typical steps in fixing the problem but there is one thing I still don’t get about this problem. Who is replacing the pads and rotors? The OP? A shop? If the OP, have you reviewed a few DIYs on BMW single and dual piston caliper pad swaps? Review the install procedure. If both sides are degrading quickly to the point where they need replacement maybe the install is off. I’d say take it to a BMW pro. Something is off. Bent parts, stuck caliper, incorrect install, don’t pour more cash into parts, put it into expertise.

[spyro512]

I'm suffering the same issue. Did you get this solved?

My car (320iX M Sport with 340mm rotors) started vibrating while braking at ~40.000km. Not sure if it used to vibrate without braking; I think it didn't, but can't recall now as I was not paying attention to that.

Swapped the rotors to Zimmermanns + pads (TRW) and 2000km later the vibration came back. There was also a noticeable vibration at 140km/h without braking and a clearly audible noise of friction, but I guess it's because the perforated discs are just noisier.

Swapped again to Zimmermanns (this time just flat rotors, not perforated) + also swapped the hubs. Pads stayed the same as the last time, as there were new (TRW).

The test drive was incredibly good, very smooth. But the car started to vibrate again while cruising at ~130km/h after only 30km. It's very slight, barely noticeable, but it's there and it will get worse for sure. No friction sound at the moment.

I lifted the car and if I rotate the tires while lifted, there is a point where it needs slightly more force.

Any ideas? You guys think that the pads might be guilty this time? They didn't solve anything when I changed them before, therefore I assume the pads are not guilty.

[Wires]

If it's vibrating without braking, then it has nothing to do with brakes. You are tossing money at the wrong problem.

Check for wheel alignment or tire balance.