Rear Axle Sensor
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Junior Member
Joined: Sep 2022
Posts: 67
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2011 S550 4matic
Rear Axle Sensor
So I had both rear struts lowered where the car was al.ost sitting on the tires. If this happens to yours and its both sides, very likely not a bad strut, more likely the arm on your sensor has broken. So this car comes with either 2 individual level sensors, one per wheel, or 1 single sensor attached to rear anti sway bar on the drivers side. Problem is they use a galvanized sheet metal clip with a ball on the sway bar. Very simple to break. The part is about $40. Problem is changing it requires removing the rear sway bar. Here's how to do it
Remove tires
Remove all hardware holding up exhaust in the rear, brackets on both sides with 13mm bolts by the rear bumper, donuts by the rear axle held by 13mm bolts, chrome tailpipes held by torx screws. Let exhaust hang as low as it will go but tie it up at it's lowest point.
Remove lower strut bolts on both sides, should be 21mm bolt and nuts.
Place a hydraulic floor jack under rear differential and support it.
Remove 4 main bolts and 4 bracket bolts for rear subframe. These are all E Sockets.
Lower subframe as low as it will go, you may have to disconnect some other stuff.
Remove antisway bar bolts and stabilizer link top bolts. Now you can carefully fiddle it out.
Install new clip with the bar in a vise. Not easy to get it closed, you need 2 channel locks. Ball faces differential, not the tire.
Now reinstall. New arm comes with ball for sensor, requires 8 and 10mm wrenches.
Voila!!
Heres a pic, i pulled the axle but it
Wasn't necessary
Thread Starter
Junior Member
Joined: Sep 2022
Posts: 67
Likes: 31
2011 S550 4matic
So I considered that but I decided against it. If the clamp ever came loosr, you would have a problem. Original lasted 12 years. I think it will be important to keep that rod lubricated
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Joined: Aug 2014
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S500
sure is - but as you found that rear one is well hidden.
Don't forget to do both front ones (these are nice and easy)... in your first post u mention how many sensors there are .... the airtragic cars get 3
Option ABC suspension - gets a sensor per corner - but no idea what type
Don't forget to do both front ones (these are nice and easy)... in your first post u mention how many sensors there are .... the airtragic cars get 3
Option ABC suspension - gets a sensor per corner - but no idea what type
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
sure is - but as you found that rear one is well hidden.
Don't forget to do both front ones (these are nice and easy)... in your first post u mention how many sensors there are .... the airtragic cars get 3
Option ABC suspension - gets a sensor per corner - but no idea what type
Don't forget to do both front ones (these are nice and easy)... in your first post u mention how many sensors there are .... the airtragic cars get 3
Option ABC suspension - gets a sensor per corner - but no idea what type
Three sensors make sense as one sensor reading the rear sway bar basically returns the average level from the rear wheels so when the car levels itself in the front it uses average sensor reading from the rear single sensor.
perhaps in mu E class it uses average value from the rear sensors...??
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S500
not saying this is how it really is - but in my experience - each damper per corner has internal sensors that you review and can adjust in Xentry (down to one mm each way [up or down] at a time)... but then somehow the car "understands" what happening most of the time from the three external sensors it has - one at the back that does rear height - the two fronts, then do whole car side to side, whilst hoping to get the front's about right
MBWorld Fanatic!
Joined: Aug 2014
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S500
...which must be interesting when they took 25kg out of the right rear corner and added 10kg to the front left in 2007 during the mini facelift? (...when they played with batteries RHD car - LHD might be the opposite corners)
