E-Class (W212) 2010 - 2016: E 350, E 550
Sponsored by:
Sponsored by: CARiD

Moaning while braking

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Oct 7, 2018 | 10:39 AM
  #1  
techtown's Avatar
Thread Starter
Newbie
 
Joined: Sep 2018
Posts: 4
Likes: 0
2015 MB E350
Moaning while braking

Posted this in W211 in error. Thanks to person that corrected me.
2015 E350 with original pads and rotors at 28K miles. Recent used car purchase from Lexus dealer. Since getting this car in July the brakes moan as brake is applied coasting to a stop. Finally took to a MB dealer that reported issue is caused by rusted rotors. The rust is on the inside of rotors Dealer suggested rotors could be changed, but still a lot of life remaining if I could live with the moaning. One representative suggested dragging on the rotors to clean off the rust. Apply the brake with one foot and accelerate with the other foot to drag the rotors thru the pads, to hopefully clean up the rotor surface. Are there better methods to clean up the rotors? Spray on cleaners? While shopping for this car I test drove other E350 sedans and wagons and several of them had the same moaning brake issue. I know rusty rotors are a problem for all cars. But is it more prevalent on MB's for some reason? Stoopid me for not having Lexus dealer fix it before I purchased.
Reply
Old Oct 7, 2018 | 11:19 AM
  #2  
dbldpr's Avatar
MBWorld Fanatic!
Veteran: Navy
MBWorld Ambassador

10 Year Member
Liked
 
Joined: Mar 2014
Posts: 6,398
Likes: 695
From: Northwest Illinois
2014 E350 also restored: 1969 Camaro convertible SS 1957 Chevy Belair 2dr hardtop
Actually by dragging it might clear up the rust. I have seen a lot of MB cars with rusty brake rotors. Mine are like new but then the car is rarely out in the rain. I have heard that you can use a Grinding disc to clean the rotors but I have never done that. Sorry I could not be of more help.
Reply
Old Oct 7, 2018 | 11:45 AM
  #3  
ot1's Avatar
ot1
Super Member
 
Joined: Apr 2007
Posts: 633
Likes: 48
From: USA
2006 E320 CDI
Originally Posted by techtown
Posted this in W211 in error. Thanks to person that corrected me.
2015 E350 with original pads and rotors at 28K miles. Recent used car purchase from Lexus dealer. Since getting this car in July the brakes moan as brake is applied coasting to a stop. Finally took to a MB dealer that reported issue is caused by rusted rotors. The rust is on the inside of rotors Dealer suggested rotors could be changed, but still a lot of life remaining if I could live with the moaning. One representative suggested dragging on the rotors to clean off the rust. Apply the brake with one foot and accelerate with the other foot to drag the rotors thru the pads, to hopefully clean up the rotor surface. Are there better methods to clean up the rotors? Spray on cleaners? While shopping for this car I test drove other E350 sedans and wagons and several of them had the same moaning brake issue. I know rusty rotors are a problem for all cars. But is it more prevalent on MB's for some reason? Stoopid me for not having Lexus dealer fix it before I purchased.
the moaning is coming from vibration of the pad. Causes: damping compound was not used between pistons and pads, or rotor may have an outside lip, or some grease or tar from road or cv boot split got on the rotor. Some oreilly have the rotor lathes to resurface the rotor $25, to get to possible rotor contamination you have to pull the callipers to get to the inside surface, use chlorinated brake cleaner, and blue scott towels. And since the caliper is pulled use the antivibration/dampening compound. Don’t put crappy china rotors on your vehicle, go to fcpeuro for german rotors. A picture of how much rust would be helpful. Light rust should clear up as you drive. Also you could have air in the caliper, so bleed it. Have you have the brake fluid replaced yet?


Last edited by ot1; Oct 7, 2018 at 11:50 AM.
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 06:11 AM.

story-0
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know

Slideshow: Mercedes-AMG's new electric GT 4-Door Coupe trades combustion for software, synthetic noise, and more than 1,100 horsepower.

By Verdad Gallardo | 2026-05-20 20:08:15


VIEW MORE
story-1
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-2
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-3
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-4
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-5
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-6
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-7
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-8
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-9
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE