Golf/Octavia Brake Vibration: Causes & Fixes

Hello,

I'm experiencing a strange phenomenon.

The brake sometimes pulsates or vibrates slightly when lightly applying the brakes.


The rotors and pads are expensive brand-name parts (TRW) and have approximately 70,000 km on them. The remaining pad thickness is around 50-60%, due to mostly highway driving. The rotors are perfectly smooth with no grooves, edges, or imperfections. Additionally, the hub seats are completely verschandeln and flat.

So far, the car has never had any problems with brake judder – which is strange because it sometimes happens and sometimes doesn't. This means that on a single trip, it might exhibit brake judder at one point but not at another.


Regarding the suspension, everything is checked and secure. The brakes were recently disassembled, completely cleaned, and lubricated; the brake pistons moved very smoothly.

The only thing I noticed was that the areas where the saddle "wings" grip onto the seat post clamp were recessed by about half a millimeter. But replacing the seat post clamps preemptively can't be the solution to the problem, right?


Does anyone have any experience with the FS-II brake (280mm)?


Greetings.

Hello Ibiza!

"...empirical values don't really tell you much, but I would first try swapping the wheels diagonally or installing a different set of wheels and observing any changes in behavior before directly addressing the brakes."

Best regards from Munich!

Quote:

The rotors and pads are expensive brand name parts (TRW) and have now been used for over 70,000 km. The remaining brake pad thickness is around 50-60%, as they have only been used for long distances.

I also had similar experiences with a Passat 3C.

I will no longer voluntarily install TRW brake parts.

I think an exchange of ideas is unavoidable if we want to achieve peace and tranquility.

Experiences... Well, in a Fiat Stilo belonging to a friend of mine, this also happens when the brake pad thickness is between 50% and 75%. It doesn't matter where the brake parts came from. The brake calipers were easy to move, and the guides had absolutely no play.

A complete replacement would be the ideal solution. Alternatively, you can swap the brake discs and pads from one side to the other, as we did. This way, the pads end up in their original mounting positions (inner/outer), but on the opposite side. The pads can then be used until they reach their wear limit. The braking noise that occurs during light to moderate braking only appears as a wear indicator when the pads are nearing the end of their lifespan.

With a single set of brake discs, you can typically use two sets of brake pads, and rarely a third. The direction of rotation needs to be reversed approximately every 25-35 thousand kilometers. By rotating the brake discs, you also avoid the pronounced seizing of the brake discs on the hubs, which otherwise always made removing them quite difficult. The usage profile is roughly 80% city driving and 20% highway driving.

Does it happen every time when the brakes are warm, or is it inconsistent?
The rotor is stainless steel and the disc sits perfectly flat. However, I have a slightly larger brake system. Sometimes, the outer portion of the brake pads (used for the last 2 to 5 thousand kilometers) may only be used minimally, so slight vibrations can occasionally occur during strong braking (pay attention to your rearview mirror; avoid doing this in heavy traffic). I only started experiencing this problem when I replaced the original rotors with ATE Powerdiscs that I had stored in my basement at around 228,000 kilometers... I'll never do that again. However, I also don't think I'll ever change the brakes on this car again ... we'll see!

"I'm familiar with that too. This occasional and slight vibration often occurs after a certain mileage, even if the wheels were perfectly round before. So far, cleaning the contact surfaces on the hub, disc, and rotor has always helped. Sometimes, it was also necessary to re-center the wheel on the hub."
Do you have aluminum rims or steel rims with hubcaps? The latter can also contribute to vibrations if they are not properly centered.
hg
Herbert.

Thank you all for your comments.

DieselBär30x wrote:

"...empirical values don't really tell you much, but I would first try swapping the wheels diagonally or installing a different set of wheels and observing any changes in behavior before directly addressing the brakes."

Yes, I've already tried adjusting it, recalibrating it, and even swapping parts, but nothing has worked.

Autoservice wrote:

I will no longer voluntarily install TRW brake parts.

Overall, I've always been very satisfied with ATE and TRW products, especially considering that the problem occurs repeatedly throughout the day.

matthiasTDI96 wrote:

Does it happen when it happens, always with a warm brake system, or is it diffuse...? The

scar is rust-free, and the

Herbert wrote:

disc lies flat and properly. I believe it only happens when the brakes are hot. Also, for the past 3000 km, I've been driving with a full load – four people plus luggage. However, it's only on country roads and there hasn't been any hard braking involved. The rotor is rust-free and the disc sits perfectly flat.

Previously, a solution has always been to meticulously verschandeln the surfaces of the hub, disc, and wheel rim; sometimes, it was also necessary to rotate the wheel on the hub.
Do you have aluminum rims or steel rims with hubcaps? The latter can also contribute to vibrations if they are not properly centered.
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Original alloy wheels, new tires (Pirelli P7 Cinturato), freshly balanced to rule out any imbalance issues.

Front/rear wheel set swapped for testing > no improvement. Hub surfaces are perfectly clean.



Here's another thought: If I'm constantly driving with a total weight of almost 2 tons right now, and the brakes are already worn down by 50%, then the brake discs will also be thinner, dissipate heat less effectively, and that can lead to this temporary overheating. Then, if you don't use the brakes for a while, it goes away again.

Interestingly, the brake only pulsates when you're initially applying it. When you press down firmly, it brakes perfectly.

I had a similar problem on an E46; the rattling only occurred when braking lightly.
For me, it was a fixed bolt from the saddle. Are you sure everything is properly aligned and clean?

Yes.

"Definitely sure. I don't have that old-fashioned system with sliding bolts and rubber bushings that slide within the saddle clamp, but rather the FS-II braking system with the threaded sliding bolts on which the brake pads slide."

They are absolutely spotless, well-oiled, and the saddle is completely functional. However, I'm still leaning towards considering replacing the worn saddle supports.

As I mentioned above, at the points where the surface panels meet, the holder has recessed on both sides.

Quote:

As I mentioned above, at the points where the surface flanges rest, the holder has been deformed inwards on both sides.

Are we talking about FSIII and not FSII? If so, it would be the version "without brake caliper mounting bracket" (standard Golf 4 brakes), where the caliper is directly screwed to the wheel bearing housing.

These blocks always have some space above and below them.
If, for example, the material of the brake pad carrier and the axle knuckle are incompatible, or if the pads are undersized, it will naturally encourage the pads to shift within the caliper bracket. The same applies if the brakes are rubbing.
Whether this excessive play leads to braking problems would need to be assessed visually.

From a distance, I would guess that the coating hardens. When it's warm, it initially rubs or vibrates on the disc before settling down again under increased braking pressure.

Okay, I don't waste any time with that kind of thing. Experience has taught me otherwise. We only use parts from original equipment manufacturers, except for... and we never buy products from so-called "packers."

"Those who remember the great brake pads from Lucas (green packaging) know what I'm talking about. Out of the 10 pairs I installed, none of the pads lasted until the end. However, Lucas brake calipers and hydraulic brake boosters are top-quality products."
It is likely well-known that what was once Lucas is now TRW.

It's fair to say that TRW brake pads generally perform well on Opel vehicles.

"You're right, it's an FS-III. My Seat had an FS-II. They are the ones that are essentially screwed into the wheel bearing housing, just like you said."

I'm just not sure right now whether the seat post holder is a separate part or if it's actually integrated with the wheel bearing housing. If it's the latter, I don't have to worry about the worn areas because it definitely wouldn't be cost-effective to replace the entire assembly.


I'm not planning on replacing the brakes just yet; they still have about 50% of their lifespan left. Based on my driving style, that translates to roughly 50-60,000 kilometers (or miles), which means these will definitely be the last brakes I install on this car.

I don't want to invest any more money into the Octavia than is absolutely necessary, and I certainly won't be paying for customer service features.

Unfortunately, my uncle's 1998 Octavia with a 90 hp TDI engine had brake judder until he sold it at 370,000 km. He replaced the brake discs multiple times, as well as the control arms, shock absorbers, etc.
Nothing helped.

My A3 from the same year, also with an AGR engine and the same brakes, never experienced this issue, even with 300,000 km on the clock.
It seems to be a problem specific to the Octavia.

Currently, it's been completely quiet for almost 2000 kilometers... you just can't understand this car.