Scraping noise from under car. New cause + solution
02-15-2017, 04:33 AM
#1
Super Member
Thread Starter
Scraping noise from under car. New cause + solution
I had a metal on metal rotational scraping noise from under my car. I pulled the rear rotors several times, turned them on a lathe, replaced pads, inspected wheel bearings, quadruple checked the dust shields, scoped the heat shields, etc. Finally I put the car on the lift again, suspecting the worse (transfer case output bearing or getting lucky and the drive shaft center support bearing). I put the car in gear and spent 15 minutes with a stethoscope under the car. The noise was coming from the drive shaft but was not contacting anything (mileage is in the 48k range now).
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
02-16-2017, 10:51 AM
#3
MBWorld Fanatic!
Join Date: Jun 2013
Location: Sacramento , CA
Posts: 1,900
Received 196 Likes
on
171 Posts
2010 e550 p2
I had a metal on metal rotational scraping noise from under my car. I pulled the rear rotors several times, turned them on a lathe, replaced pads, inspected wheel bearings, quadruple checked the dust shields, scoped the heat shields, etc. Finally I put the car on the lift again, suspecting the worse (transfer case output bearing or getting lucky and the drive shaft center support bearing). I put the car in gear and spent 15 minutes with a stethoscope under the car. The noise was coming from the drive shaft but was not contacting anything (mileage is in the 48k range now).
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
**** , i wish i had a lift available at no cost when i need it lol
02-16-2017, 02:09 PM
#4
Super Member
Thread Starter
Yeah, It's a lifesaver. I love having keys to a "real" shop! Considering that at home I don't even have a garage, it makes things much much easier. (aside from the 25 minute drive each direction).
I just landed shop access but no keys to another friends spot. He has a road force balancer which is going to be damn handy when I mount up my new summer wheels in a week or two when they arrive!
I just landed shop access but no keys to another friends spot. He has a road force balancer which is going to be damn handy when I mount up my new summer wheels in a week or two when they arrive!
02-17-2017, 10:55 PM
#5
Super Member
Join Date: Sep 2015
Location: Cleveland OHIO
Posts: 638
Likes: 0
Received 36 Likes
on
35 Posts
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
I had a metal on metal rotational scraping noise from under my car. I pulled the rear rotors several times, turned them on a lathe, replaced pads, inspected wheel bearings, quadruple checked the dust shields, scoped the heat shields, etc. Finally I put the car on the lift again, suspecting the worse (transfer case output bearing or getting lucky and the drive shaft center support bearing). I put the car in gear and spent 15 minutes with a stethoscope under the car. The noise was coming from the drive shaft but was not contacting anything (mileage is in the 48k range now).
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
I ended up loosening the center support bearing carrier and dropping the tail end of the driveshaft. Using a snap on scope camera and a magnet, I cleared out a large amount of metal flakes and rust debris. The outside of the shaft is not rusted either which is very odd.
Either way, if you have a strange dragging/scraping noise and can't isolate it, perhaps this is your issue. It's easy enough to check (unbolt the rear flex disc, loosen the center support and the shafts can be dropped down).
I dodged a bullet on this one for sure!
02-18-2017, 03:18 AM
#6
Super Member
Thread Starter
It was not more or less apparent when turning.. it sounded exactly like a driveshaft rubbing on a heat shield, or a rock between a brake dust shield and rotor. I have a video I can upload to flickr and link here if needed.
If you are experiencing something similar, her your car on a lift. You can take a stethoscope and put it on the pinion output bearing in each differential, the transfer case outputs and the center bearing carrier as well as the heat shields and back of each brake rotor/wheel bearing. (Car running and in gear). If the shaft isn't rubbing anywhere and nothing seems louder or rough/grinding, it is worth checking out. I literally pulled apart the rear brakes 4 times before finally figuring out that wasn't the issue.
If you are experiencing something similar, her your car on a lift. You can take a stethoscope and put it on the pinion output bearing in each differential, the transfer case outputs and the center bearing carrier as well as the heat shields and back of each brake rotor/wheel bearing. (Car running and in gear). If the shaft isn't rubbing anywhere and nothing seems louder or rough/grinding, it is worth checking out. I literally pulled apart the rear brakes 4 times before finally figuring out that wasn't the issue.
03-14-2017, 04:17 PM
#7
Newbie
Join Date: Apr 2013
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
500 SEL, 500SL, 500G
did you ever upload the flicker video of the car and sound, i have a similar issue with my e320 which sounds almost identical. was thinking about having my drive shaft balanced thinking this is the vibration issue which in turn sounds like could be a metal to metal sounds secondary to the vibration and source of the sound. thoughts.
