Unusual Brake Rotor Damage (pics)

[Wave Grease]

Originally Posted by Moppie

Are you sure you weren't driving beside a truck when it happened?

That video is showing the noise from a diesel engine brake.
They basically block the exhaust with a valve that builds massive compression in the engine, which exaggerates any engine braking effect while it's in gear.

No, its been happening for all 56,000 miles I've been driving the car. It is just a coincidence that the sound is so similar. In addition, Trucks in Germany dont have loud jake brakes.

[Wave Grease]

Unfortunately, the noise persists.

[Moppie]

Originally Posted by Wave Grease

Unfortunately, the noise persists.

Have you had the wheel bearings checked?

[Wave Grease]

Wiggle the wheel up and down and check for play right? I'll try this. I figured bad bearings would make themselves known even without braking.

[Moppie]

Originally Posted by Wave Grease

Wiggle the wheel up and down and check for play right? I'll try this. I figured bad bearings would make themselves known even without braking.

In theory yes, but not always.
I have a bearing in my car that is going bad, but the noise goes away under braking or acceleration.


Jack the car up and put it on solid axle stands, or a large block of solid wood.
Do not leave it on the jack.

Then grab the wheel and give it a good wiggle in all directions. There should be no movement.

Also spin the wheel. It should run very smooth, with only slight noise from the CV joints, and it should run down at a consistent rate till it stops.