Groaning and moaning brake pedal
Thread Starter
Senior Member
Joined: Oct 2005
Posts: 352
Likes: 1
From: fl
1992 500E, 2006 E500, 2007 GL 450
Groaning and moaning brake pedal
Since new, my 2006 E500 has periodically developed a groaning noise in the brake pedal. It did not matter if the car was moving or in park. The noise is quite load and can easily be heard above the radio. Could not repeat for the dealer. SA thought it might be normal. Yesterday it became particularly annoying I put the car in park and stabbed the pedal with extreme prejudice. After 40 or 50 jabs the noise vanished.
Member
Joined: Jun 2006
Posts: 125
Likes: 0
From: Los Angeles
w211 E320
Since new, my 2006 E500 has periodically developed a groaning noise in the brake pedal. It did not matter if the car was moving or in park. The noise is quite load and can easily be heard above the radio. Could not repeat for the dealer. SA thought it might be normal. Yesterday it became particularly annoying I put the car in park and stabbed the pedal with extreme prejudice. After 40 or 50 jabs the noise vanished.
Try this, while the car is stationary press your brake pedal twice, dont do it too fast but do it twice and if you hear the light vibrating sound its definitely the SBC system. Theres also another type of sound I heard from my car before which is a low fast rumbling sound but it usually happens when I cross the train tracks or something bumpy and thats normal btw. But if you are driving on the freeway and you hear it above the radio then its abnormal, this shouldnt be occuring at highspeeds.
Thread Starter
Senior Member
Joined: Oct 2005
Posts: 352
Likes: 1
From: fl
1992 500E, 2006 E500, 2007 GL 450
I did not make it clear in my post that the groan occurs when I hit the brake pedal and is independent of how hard or long I brake - it is a loud sound and it occurs when initially hit the pedal, it does not matter if the car is park or moving. I am familiar with the SBC pump sound - this is different. The problem may be unique, when it happens again I am just going to smash the brake pedal until something breaks and the dealer can repair it.
Out Of Control!!
Joined: Jul 2003
Posts: 15,901
Likes: 4,632
From: North Scottsdale, AZ
'71 Pinto
I did not make it clear in my post that the groan occurs when I hit the brake pedal and is independent of how hard or long I brake - it is a loud sound and it occurs when initially hit the pedal, it does not matter if the car is park or moving. I am familiar with the SBC pump sound - this is different. The problem may be unique, when it happens again I am just going to smash the brake pedal until something breaks and the dealer can repair it.
Noises associated with the SBC system can be identified through STAR diagnostic flowcharts (i.e.: EDAC – SBC Noise Diagnostic Tree); the SBC Flowchart focuses on noises unique to the SBC hydraulic unit, while the SBC BOU Flowchart focuses on brake operating unit noises.
While in, mention DTB P-B-42.10/51e for precaution and they will inspect the front brake discs and pressure retaining springs for contact. Front brake squealing/grinding noise may be heard even when the brakes are not applied. Brake lining, piston damper, and retaining spring will be inspected and replaced if necessary.
