2012 Mercedes-Benz E-Class Brakes Problems

Brake failure due to leaking brake fluid after dealership conducted rear sub frame extended warranty coverage replacement and recent brake fluid services and after two (2) multi point inspections including video and reported “no items failed” and “no items cautioned.” Vehicle was released to me both times Vehicle was inspected and is available for further inspections. My safety was jeopardized due to brake system failure while traveling at high speed on public highway. The problem was confirmed by two (2) dealerships. “ Please see below for recommended repairs on your 2012 E350, VIN - [XXX] Inspection by a different Mercedes Benz dealership reported the following: [XXX] Concern – vehicle is leaking brake fluid from behind the drivers front wheel / tire Cause – Confirmed concern, installed vehicle on lift and found brake fluid dripping from plastic side panel under the drivers door. Brake fluid flush recently completed on vehicle by Portsmouth MB, verified bleeding valves on calipers are tight and not leakingRemoved paneling and found fluid is dripping from wheel well area. Removed left front wheel well cover, and found rear brake lines are leaking due to heavy corrosion and bubbling (see attached photo). Correction – Rear brake lines need to be replaced to repair. Due to corrosion, will require brake hoses due to rotted connections. Lines are formed, fitted and secured by technician during repair (they do not come pre-formed to vehicle). Repair Estimate – Labor ($199.88 / hr) 9 hours (includes diagnostic time), $1798.92 Parts, estimate $690 if no further connections are needed (tax included) Shop supplies, $26.95 Estimate $2520 total repair **Tech notes there is a fuel line running in an area of the brake lines that is showing bubbling in the metal, not yet leaking. Additional $375 parts and labor to replace if we replace with the brake lines. MB parts states there are only 2 of these lines remaining globally.” INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The brake lines on my car rusted out from the brake booster all of way to the rear calipers. This is the third time it’s happened to me as I’ve owned multiple E classes. If Mercedes-Benz covers the subframe, why is the brake lines which are located right above said subframe not covered?

I recently took my 2012 Mercedes-Benz E350 to an authorized Mercedes-Benz dealership after experiencing corrosion of the rear subframe. The dealership confirmed and is servicing the vehicle under an active recall notice that extended the original New Vehicle Limited Warranty from 4 years/50,000 miles to 20 years /unlimited miles. After removing the subframe for repair, they observed serious corrosion of the brake lines. There had been no warnings or symptoms to alert me to any corrosion problems with the brake line prior to this. Most likely, the issue would not have been discovered if the dealership had not removed the subframe. The dealership advised me that this issue requires immediate service due to safety concerns (potential failure) as the braking system could fail while driving the vehicle. The cost to have the work done is $5800. Beyond the dealership service center, I'm not aware if brake line has been inspected by others (engineers) in Mercedes-Benz. However, this issue appears to be frequently observed in vehicles experiencing the rear subframe corrosion issue.

2012 e350 both rear brake metal lines rusted out January 2025 brakes gave out. This is definitely connected to the rear subframe rusting too.

The contact owned a 2012 Mercedes-Benz E550. The contact stated while her husband was driving 20-25 MPH and making a right turn, the brake pedal was depressed but traveled down to the floorboard, and the vehicle failed to respond. The contact's husband stood on the brake pedal; however, the vehicle failed to respond and crashed into a small ditch. The contact was occupying the front passenger's side seat at the time of the incident. The contact was unsure whether there was a warning light illuminated. The air bags deployed. The contact stated that there was smoke coming from the air bags. Both the contact and her husband immediately exited the vehicle. The contact's husband did not sustain any injuries. The contact stated that her left arm was deformed. The contact was transported to the Hospital by a family member. The Doctor diagnosed that the contact had sustained two broken bones on the left arm and two broken bones on the left foot. The contact underwent surgery and was scheduled for physical therapy. The contact was unsure whether a police report was filed. The vehicle was towed and totaled by the insurance company. The dealer was not notified of the failure. The manufacturer was notified of the failure and advised the contact that a field inspector would be sent to inspect the vehicle. The failure mileage was unknown.

Rusted/leaking brakes lines to rear of vehicle.

The contact owns a 2012 Mercedes-Benz E350. The contact stated while driving at various speeds; when the brake pedal was depressed, the brake pedal failed to return to the original position. The contact stated that upon inspection, the brake pedal felt abnormally loose and there was a brake fluid leak present. The vehicle was taken to an independent mechanic where it was lifted and was noticed that the sub-frame was rusted. An appointment with the dealer was scheduled to inspect the vehicle as a second opinion. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 160,000.

BRAKE LINES TO THE REAR HAVE CORRODED AND CAR CAN NOT BE DRIVEN.

The rear brake lines on my 2012 Benz E350 has a lot of corrosion and one of the blowout while stopping from 25mph to a complete stop. Upon further inspection, it was completely rusty in many places. Mercedes needs to address this issue because its unsafe rather danger to drive.

Brake line corroded under protective cover. Was driving and felt mushy brakes and came home to almost no brake fluid. Found leak under driver side door. Kind of weird because it’s under a cover.

My car had a pool of brake fluid under the car and when I turned it on, it said the brake fluid was low. When I went to check the reservoir it was empty. The underpanels were removed and the brake lines were rotted out in several areas. I was shocked because my car is in mint condition and I have always avoided taking it out when the roads are salted in the winter. I am lucky this happened when the car was parked. This has never happened to the cars in my family which were never treated with as much care.

RUSTED BRAKE LINES CAUSING BRAKE FLUID LEAKING AND LOOSE BREAK PEDAL. THIS IS SEVERELY AFFECTING BREAK SYSTEM PERFORMANCE AND VEHICLE SAFETY. MB DEALER QUOTED $2910.00 PLUS TAX FOR REPLACEMENT.