Warped Brake Disc: Causes & Solutions

Hello,

A while ago, I completely replaced the front brake discs along with the pads, and everything was purchased directly from the official dealer. (It cost a lot of money.)

However, I'm not satisfied because there's a slight pulsating effect in the braking, which can be noticed when approaching a traffic light slowly and applying very gentle pressure to the brakes.

I had this problem back in the spring, and I attributed it to the wheel hub. In fact, there was some light rust on the wheel hub, and after removing it with the wire brush attachment, it improved.
It's happening again.
Either new rust has formed again, or the glass has been hit.

My question is: How do you treat the areas of the brake disc and wheel hub during the process?
I applied a very thin layer of Plastilube to prevent corrosion. Probably too thin. On the other hand, I often hear that people don't do anything at all to protect against corrosion in that area?

If the wheel hub doesn't run true, it's inevitable that the disc brake rotor will also develop runout (lateral deviation) relatively quickly.
I think it wasn't quite right from the beginning, and only the protruding parts of the glass get properly heated, which gets worse over time.
A specialized grinding disc, such as the Berner type, for use with a drill has given me the best results so far!
Accurate measurements using a dial indicator will reveal whether the cause of the problem is the disc or the hub.
Also, another thing: lubricants are not allowed under the disc, but I always applied WD-40 or Caramba to the hub and wiped it off.

Hello teileklaus,

I'll be putting on the winter tires soon, and then I'll lower the window again.
Your explanation makes sense to me.

What kind of grinding disc is that? Is it a wire brush attachment, or what's commonly called a "chocolate chip" (referring to a type of abrasive), or a sandpaper attachment? Which one are you using?

So, "running it" means keeping the wheel spinning while it's engaged? And then grinding down the hub?

I'm afraid the cutting depth of the milling cutter is too large; it might remove too much material. It also shouldn't create an uneven surface due to excessive material removal.

I'm not very familiar with those edible tools .
It's a bell-shaped device with a spindle at the back for attachment to the drill, and a grinding disc on the front, resembling a black, hard "woven sponge." In the center is a recess for guiding the hub of the disc.
Is there anything available from ZB Berner?
Sure, here is the translation of the text from German to English:

"edit partial clause:"
If the hub is not working properly, replace it.

If the rust has already significantly corroded the metal, it's essentially pointless to try and fix it because the material has been lost in those areas where the rust has eaten away at it.