x166 Mercedes GLS 550 engine mount failure

Couple notes on the engine mount that failed on our 2017 GLS 550 with 44k miles (it does not have 52k like I mention in the video).

[@mikimiki195]

Dude I just wanted to say thanks for posting on forum and making this video. I just completed mount on my GL550 by following your instructions. Thanks again. 👍🏻👍🏻👍🏻👍🏻👍🏻

[@manuelfrank8866]

Easier way to do the passenger side… Hey Guys! Just replaced mounts yesterday (what an ordeal). However, found an easier way to deal with the passenger side Mount removal! Thanks to a friend that happened to be on the front of the vehicle jacking the motor up and down. He pointed to some space accessible from the front side of the engine. You can easily remove the Mount by removing a lower air duct from the front passenger side of the engine, you will find space to get the Mount through there. After removing that lower air duct, the only obstruction is the plug that is connected to the alternator. Just unplug it and voila! The Mount fits through!! You still have to remove the catalytic Converter to access the Horizontal motor Mount bolt. It just makes it easier to get it out and in from the front. Another suggestion, I attached both mounts using the horizontal bolts, and it was a pain lowering the engine and making sure they both will sit properly on the chassis. If you have the chance, buy 4 much longer bolts with the same thread as original 4 mounting ones. And attach them to the mounts, always trough the original subframe holes for alignment, the excess bolt length will help guide the mounts on their way down when you lower the engine. Once the mounts are fully and properly seated, remove the bolts and instal the original ones. Without this you will require someone to be jacking the engine up and down while you push the Mount around to make it sit properly. Forgot to mention, this is on a x166. A 2015 GL550. Hope it helps! In case I make changes to the post, you can read it here. mbworld.org/forums/gl-class-x166/760638-gl550-bad-engine-mounts-procedure-replacement.html#post8819055

[@daveh2612]

There's a KZbin video of a guy doing mounts on a 2014-2016 E63 and he realized the same thing. Passenger side mount comes out easiest through the front.

[@mekantor]

I tried for hours to do the passenger side and had to give up. Left the bad one in there, but replaced the driver side. Did you lift the motor from the top with the lifting eye, or jacked it up from the bottom? I need to try again soon once I forget how bad it was. I was thinking of pulling the half-axle there to make space for the mount to come out.

[@Billium632]

@@mekantor I jacked the motor up from underneath all the way until the back of the motor was touching the firewall. And even then, I had to rock the engine by hand up out of the way to BARELY have enough room to remove and then replace that one.

[@mikimiki195]

I just stumble up on this video on forum. I just got 2015 GL550 56k miles Fucking think have bad mount. At what point if lift did you use jack to jack up the engine. Did you have top engine support or you just had jack from the bottom? Did you remove exhaust? I know too manny questions but I have to do this crap and not looking forward Thanks

[@AZMTB]

I just used a big floor jack and a piece of 2x4 wood block under the lower oil pan. After getting both downpipes off (really not that difficult) the biggest pain was just removing some of the heat shield bolts which you have to get out of the way to get at the engine mount and the engine mount bolt on either side. After you've got the heat shields out of the way and the mount bolts out, I went back on top of and removed the air intake boxes because they would be the first things to contact the firewall. I jacked up the engine all the way to where some components in the very back were just touching the firewall padding. Back underneath, I removed the two bolts that face downwards on both mounts (easily accessible from underneath the car), then on the passenger side, I had to get a pry bar and rock the engine over to the driver's side which gave me JJJJJJJJUST enough space to wrangle the engine mount out. It barely came out and the new one barely went back in, but it did after some fighting. Have to make sure it's rotated so that tab ontop of the mount is pointing outwards. The driver's side was much, much easier like I said in the video. Just left the engine jacked up in the air, grabbed the old one and got it out no problem and the new one in no problem at all. Lowered it back down and everything bolted back up no problem. I'd get a ratcheting e-torx wrench for the size 8 heat shield bolts, otherwise they're next to impossible to get at with your fingers to remove and reinstall them. I'd recommend just doing the driver's side mount unless both seem totally dead.

[@mikimiki195]

@@AZMTB great idea on removing air intake boxes well I will be working on 2015 GL550 but I think it’s for most part same I might have to remove half axle on passenger side but I don’t think I will be doing passenger side considering car only have 58k miles. I think I will only do driver side. Great writeup thanks a lot. 👍🏻👍🏻👍🏻👍🏻👍🏻