Hey guys, I have not posted on the forum since my initial post in Feb. 2017 but have greatly benefitted over the years from the information shared here. My wife's little 05 Kompressor is more of a "third car" nowadays but would have long been in the junkyard if not for those that have contributed to this site. So thanks! The car recently developed a shake in the engine that would send a strong vibration through the cabin when in Drive or Reverse while also sitting still. I was able to find some motor mount DIY info out there but it was mostly inconclusive or for similar year Benz's without the M271, and it did not answer the questions I had before starting the job. So hopefully this will help those who run into a similar situation.

1) Consensus seems to be the Corteco or Lemforder motor/trans mounts are the way to go (possibly OE suppliers?). The driver's and passenger's mounts are identical minus the silicone heat shield that goes on the passenger side mount to protect from the exhaust manifold's heat. I had seen the mounts listed as different part numbers in one place, but this must have been to account for the driver's side not needing the shield. The Corteco pair I ordered ($135.98) were the same part # and both included the shield (which you don't need on the driver's side). I recommend replacing the transmission mount at the same time as it is inexpensive ($22.69) and easy to complete(four bolts with no need to remove the bracket).

3) You do NOT need to remove the intake or supercharger for the driver's side as indicated in the Mercedes workbook! Thank Goodness! You will be accessing the driver's side mount between the trans and trans tunnel - the space is relatively tight. There is an A/C line bracket attached to the transmission with two E-Torx (E10?) bolts that needs to come off so you can maneuver the line to work the mounts in and out. The mount takes some wiggling but will come out.

4) The "special tool" may or may not be necessary for the bolt on top of the driver's side mount, but it certainly helped. I used the Baum Tools (001-0016/2) 16mm Benz engine mount wrench ($32.49). You may be able to recreate something similar with a cut off 16mm or 5/8" box-end wrench but it may be difficult to get the correct shape and necessary torque to remove the bolt. I started with a 1/2" drive 24" breaker bar w/ adapter on the special tool but could not get it to the correct position on the head of the bolt. After attaching to a normal size 3/8" drive ratchet, it was not hard to get on it and break it free. Then, I took advantage of a 5/8" flex-head ratcheting wrench to run it out.

5) The passenger side mount also took some effort to fish out as well, but I was able to get it out without removing the exhaust or mount bracket from the block. After removing the top bolt, weight, and metal heat shield, you will need to also remove the silicone heat shield covering the mount in order for it to squeeze in between the manifold and bracket. Like the driver's side, it is a tight squeeze but can be done with patience and effort.

Watch out for the small rubber o-ring(s) the top mount bolts - not sure how necessary the are but I had one that needed replacing. Bottom bolts on both engine mounts are relatively easy to get to (13mm). I did not measure the torque when reinstalling but did use blue loc-tite and firmly tightened everything. Taking the front driver's wheel off seemed necessary to access D-side mount - passenger wheel can stay on. Remember to use some sort of insulation (like a wooden block) to insulate between jack and oil pans. For the trans mount especially, I recommend using a 1"-2" thick piece of wood slightly larger the transmission pan so there isn't too much pressure on any one spot (does not require as much lifting as engine). Please also use proper jacks and jack safety when raising and working underneath your vehicle.

While doing the mounts stopped the vibrations from being transmitted to the cabin, the engine still had a rough shake (no misfires or codes) at idle when in Drive or Reverse that, to me, mimicked the symptoms of bad mounts. The fault actually ended up being a seized alternator pulley. There were no charging issues but the alt. pulley is supposed to freewheel in one direction. Replaced that, and the car feels incredibly smooth. So much so I have check the tach to see if it's running at idle! Dealership quoted $1800+ for all three mounts, so I'm pleased coming in at $200 (including tool) and a couple hours in the driveway. If I can help anybody else tackling the same job, please feel free to reach out. Attaching several pictures below. Thanks again fellas!