What Causes the Brake Squealing in Mercedes-Benz E300?

[DeAlivia]

Brake squealing occurs due to reasons such as worn brake pads leading to the backing plate grinding against the brake disc, hardened brake pads, or foreign objects lodged in the brake pads. Below are detailed explanations of the causes: Introduction to Checking the Causes of Squealing: When encountering squealing, the first step is to inspect the thickness of the brake pads, as this is fundamental to ensuring driving safety. Even if the brake pads are not worn thin, they may still produce noise during braking, similar to the sound of grinding against the wear indicator. This is caused by larger metal particles within the brake pads rubbing against the brake disc, resulting in a metal-on-metal friction sound. This is a normal phenomenon and does not indicate any quality issues with the brake pads. Other Causes of Brake Squealing: During the break-in period of a new car, the bedding-in of the brake pads is a crucial phase. Typically, after driving a few hundred kilometers, the braking performance will feel more comfortable. Similarly, newly replaced brake pads also require a break-in period to better integrate with the existing brake disc. Initially, the brakes may feel very stiff, and it usually takes a few hundred kilometers of driving before they start to feel better.

[Carol]

When I first drove my Mercedes-Benz E300, I encountered brake squealing. The sound was extremely harsh, like metal grinding. Generally, this is mostly due to excessive wear of the brake pads or dust and small stones stuck on them. My car was more prone to squealing after rain because moisture caused metal rust, increasing friction. Sometimes, newly replaced brake pads need a break-in period of a few hundred kilometers, during which noise can also occur. If this issue is ignored and the squealing persists, it may scratch grooves into the brake discs, not only increasing repair costs but also affecting overall braking performance. I recommend regular inspections at the shop, especially checking the thickness and cleanliness of the brake pads, which can prevent small issues from becoming big problems. In daily driving, try to minimize sudden braking habits to avoid dust accumulation.

[StChristian]

I think brake noise is quite common on the Mercedes-Benz E300, not just because of the vehicle itself, but also related to driving habits and environmental factors. For example, if the brake pads contain more metal material, they are prone to producing high-frequency noise; or if the brake disc surface is uneven with fine scratches, it can cause squeaking during friction. I've encountered this several times myself, especially noticeable in winter, possibly due to temperature changes. The solution is to have a professional technician inspect the brake system and replace components or adjust lubrication if necessary. Remember not to use inferior parts—genuine parts may be more expensive but have a longer lifespan. During routine maintenance, keep the wheel interior clean to reduce sand and stones from entering the brake gaps, which can also lower the chance of noise.

[NorahLynn]

Brake noise in the Mercedes-Benz E300 should not be underestimated, as it relates to driving safety. If sharp sounds occur during braking, it may indicate inflexible movement of the caliper piston or poor adhesion of the brake pads, affecting braking performance. Once, while driving, I heard an abnormal sound and immediately went for inspection, only to find that a loose wiring connector caused a signal malfunction. If encountering similar issues, it is recommended not to delay; pull over immediately to check basic items such as brake fluid levels and tire condition. For prevention, choosing high-quality brake components and ensuring proper installation can save both money and hassle compared to post-failure repairs.