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I just noticed how different the passenger side mount looks vs. driver side.
Is it worn or just an optical illusion based on the photo being taken from above engine?
@05-E55
I don't think so. Neither looks collapsed. If you have no new noise, vibration, or harshness, I would say they are good. When I had a motor mount fail, I would notice a distinct vibration between 1100 and 1500 rpm. Not bad, but different from the usual feel. Pulled out my borescope and confirmed the mount was leaking fluid on the top side. Photo below compares a good versus bad(!) mount. This was on my W210 E55 but the mounts are the same.
If you decide to change the motor mounts yourself, a few tips:
-Disconnect the battery! The alternator hot lug is only about 1/2" away from where the rachet extension will route to the motor mount. This applies to the W210 and W211 E55.
-Special crowfoot wrenches are available for removing the upper 16mm bolt. Makes it much easier than attempting to use a box/open end wrench.
-On the W211 E55, wooden block under the oil pan or hang the motor (using a hoist) to raise it an inch or so. Unbolt the steering rack from the front subframe and let the rack hang down. Dropping the steering rack down gives you room to slide the driver's side motor mount out of the engine compartment. Unbolt driver's side motor mount and slide it across the front of the engine bay from driver's side to passenger side to remove. To install the new driver's side mount, feed it in from the passenger side, slide it across the front of the car to the driver's side, install and torque the bolts.
When I did it before left and right were the same part number.
Driver Side mount in your description looks done. Notice the engine arm sitting closer to the body of the mount vs passemger side mount.
I second the recommendation to do both motor mounts and the trans mount while you are at it.
When the heavy engine-tranny sit on collapsed mounts, it over works the the prop shaft center bearing that helps workout the rear diff input shaft bearings.
Buying quality parts with FREE REPLACEMENT makes it a no brainer to maintain parts before clunking and whining begin signaling the end of service life.
The weakest mount is the one guiding the tranny output in assiciation with both engine side mounts
ALL seasonedrubberparts fail gently by becoming increasingly *SOFT* towards marginal performance ( control arms, belt, mounts, ...).
There's no real benefit to push wear items all the way beyond failure.
Last edited by CaliBenzDriver; Mar 2, 2026 at 08:00 PM.
@05-E55
I don't think so. Neither looks collapsed. If you have no new noise, vibration, or harshness, I would say they are good. When I had a motor mount fail, I would notice a distinct vibration between 1100 and 1500 rpm. Not bad, but different from the usual feel. Pulled out my borescope and confirmed the mount was leaking fluid on the top side. Photo below compares a good versus bad(!) mount. This was on my W210 E55 but the mounts are the same.
If you decide to change the motor mounts yourself, a few tips:
-Disconnect the battery! The alternator hot lug is only about 1/2" away from where the rachet extension will route to the motor mount. This applies to the W210 and W211 E55.
-Special crowfoot wrenches are available for removing the upper 16mm bolt. Makes it much easier than attempting to use a box/open end wrench.
-On the W211 E55, wooden block under the oil pan or hang the motor (using a hoist) to raise it an inch or so. Unbolt the steering rack from the front subframe and let the rack hang down. Dropping the steering rack down gives you room to slide the driver's side motor mount out of the engine compartment. Unbolt driver's side motor mount and slide it across the front of the engine bay from driver's side to passenger side to remove. To install the new driver's side mount, feed it in from the passenger side, slide it across the front of the car to the driver's side, install and torque the bolts.
FCP Euro sells the tool.
I'm still trying to chase down this vibration I feel at idle when in gear that I posted about. It goes away in N. Also after the car is fully warmed-up it's significantly less.
I haven't been able to find a vacuum leak, but haven't done a smoke test yet.
The top picture is passenger side and it just looks different than the driver side. Maybe the angle? I don't see any fluid leaking.
I saw a video where he removed them from behind. Is that possible or is lowering the steering rack neccessary?
@05-E55
I don't think so. Neither looks collapsed. If you have no new noise, vibration, or harshness, I would say they are good. When I had a motor mount fail, I would notice a distinct vibration between 1100 and 1500 rpm. Not bad, but different from the usual feel. Pulled out my borescope and confirmed the mount was leaking fluid on the top side. Photo below compares a good versus bad(!) mount. This was on my W210 E55 but the mounts are the same.
If you decide to change the motor mounts yourself, a few tips:
-Disconnect the battery! The alternator hot lug is only about 1/2" away from where the rachet extension will route to the motor mount. This applies to the W210 and W211 E55.
-Special crowfoot wrenches are available for removing the upper 16mm bolt. Makes it much easier than attempting to use a box/open end wrench.
-On the W211 E55, wooden block under the oil pan or hang the motor (using a hoist) to raise it an inch or so. Unbolt the steering rack from the front subframe and let the rack hang down. Dropping the steering rack down gives you room to slide the driver's side motor mount out of the engine compartment. Unbolt driver's side motor mount and slide it across the front of the engine bay from driver's side to passenger side to remove. To install the new driver's side mount, feed it in from the passenger side, slide it across the front of the car to the driver's side, install and torque the bolts.
FCP Euro sells the tool.
You're the expert, but I just want to ask again, this one( passenger side) looks okay?
@05-E55 I'm no expert but it looks good to me.
FWIW, I'm the type of owner who replaces everything "while I'm in there". I'm at the point in my life where I can do that. Years ago, I looked at cost vs benefit and only replaced what was bad.
I see no fluid leaks in that photo. If there is any indication of fluid leakage, replace as soon as possible because it will only get worse.
Photo of failed driver's side motor mount below using the borescope. Leakage easy to see. The upper right side of your above photo is equivalent to the upper left side of my photo below. Borescopes tend to blur the picture...
Last edited by bbirdwell; Mar 2, 2026 at 10:47 PM.
This one looks good. Notice the gap between the engine arm and mount body.
[img alt="This one looks to have seen better days. Note the smaller gap between engine arm and mount body compared to the other side.
I was thinking it could be the angle but even the heat shield of this one looks to be sitting lower.
The gap between mount and subframe also looks smaller compared to the other side."]https://cimg0.ibsrv.net/gimg/www.mbworld.org-vbulletin/1080x999/screenshot_20260303_125027_samsung_internet_eb0fd3 190cde1f856548eaa352eee18eb318e788.jpg[/img] This one looks to have seen better days. Note the smaller gap between engine arm and mount body compared to the other side. I was thinking it could be the angle but even the heat shield of this one looks to be sitting lower. The gap between mount and subframe also looks smaller compared to the other side.
This one looks good. Notice the gap between the engine arm and mount body.
[img alt="This one looks to have seen better days. Note the smaller gap between engine arm and mount body compared to the other side.
I was thinking it could be the angle but even the heat shield of this one looks to be sitting lower.
The gap between mount and subframe also looks smaller compared to the other side."]https://cimg0.ibsrv.net/gimg/www.mbworld.org-vbulletin/1080x999/screenshot_20260303_125027_samsung_internet_eb0fd3 190cde1f856548eaa352eee18eb318e788.jpg[/img] This one looks to have seen better days. Note the smaller gap between engine arm and mount body compared to the other side. I was thinking it could be the angle but even the heat shield of this one looks to be sitting lower. The gap between mount and subframe also looks smaller compared to the other side.
Good observation! I will try to look closer or from underneath.
-Gap between the raised rubber lip on the mount and the silver engine arm
-Gap between heat shield edge and top of flat side of mount body
-Gap between bottom of flat side of mount body and subframe
that raised rubber lip by the top of the mount body is there for the arm to rest on if the vibration isolator internals of the mount collapses.
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