GL 450 front suspension mystery - MBWorld.org Forums

Notices
GL Class (X164) 2007-2012: GL320CDI, GL420CDI, GL450, GL550

GL 450 front suspension mystery

 
Old 12-17-2017, 03:02 PM
  #1  
Newbie
Thread Starter
 
Join Date: Dec 2017
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
201 GL 450
GL 450 front suspension mystery

Hello folks. Very new to the forum so please accept my apologies if this has been covered. My wife’s car a 2012 GL 450 w/ 60k is having a mystery suspension problem. It’s only occurring on front but there seems to be days where you come into the garage and it is a complete low rider after parking it an hour ago but then it can sit at the regular height for a week without dropping an inch. I haven’t pulled the tires and done the soapy water test due to that fact. The other weird part is youcan be driving highway speeds and it seems to dump everything out of the system all of the sudden and then fill back up again once you slow down or pull over.

Again I apologize if this has been covered but any help is greatly appreciated.

Last edited by garettpage; 12-17-2017 at 04:00 PM.
garettpage is offline  
Old 12-17-2017, 11:04 PM
  #2  
Member
 
Join Date: Sep 2005
Location: s.f. bay area
Posts: 194
Thanks: 0
Thanked 23 Times in 14 Posts
s500 GL450 03 Z71XL Yukon 00 Volvo s80 67 396 SS velle 68 Vert Camaro 69 RSSS Vert Camaro 75 Blazer
you most likely have a leak in your airbags. You are going to have to replace one if not both. depending on your mechanical skills and tools, it can be a job done in your garage for a lot cheaper than the dealer or garage. Also look up arnott for replacements. Also watch there video on replacing the airbag
angelglo is offline  
Old 12-18-2017, 05:48 PM
  #3  
Member
 
Join Date: Jun 2009
Posts: 91
Thanked 1 Time in 1 Post
09 GL450
Can you clarify something? Does it occur for all 4 corners, or, front two only, or, front left or right only?

Has it been doing it for a while or just started?


Originally Posted by garettpage View Post
Hello folks. Very new to the forum so please accept my apologies if this has been covered. My wife’s car a 2012 GL 450 w/ 60k is having a mystery suspension problem. It’s only occurring on front but there seems to be days where you come into the garage and it is a complete low rider after parking it an hour ago but then it can sit at the regular height for a week without dropping an inch. I haven’t pulled the tires and done the soapy water test due to that fact. The other weird part is youcan be driving highway speeds and it seems to dump everything out of the system all of the sudden and then fill back up again once you slow down or pull over.

Again I apologize if this has been covered but any help is greatly appreciated.
GLguy is offline  
Old 12-18-2017, 09:56 PM
  #4  
Newbie
Thread Starter
 
Join Date: Dec 2017
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
201 GL 450
Originally Posted by GLguy View Post
Can you clarify something? Does it occur for all 4 corners, or, front two only, or, front left or right only?

Has it been doing it for a while or just started?
Sorry, front two only and probably about 4 months.
garettpage is offline  
Old 12-18-2017, 11:25 PM
  #5  
Super Member
 
Join Date: Nov 2017
Location: Bethesda, MD
Posts: 582
Thanked 43 Times in 42 Posts
2010 Mercedes GL450; 2000 Mercedes ML55 AMG; 2016 VW GLI SEL Stick!!!
Originally Posted by garettpage View Post
Sorry, front two only and probably about 4 months.

You have a leak. Albeit it could be a small one or a large one...it is guesswork until you do a proper soapy water test.

I imagine your leak is up in the higher parts of the air spring, as from what you're saying it doesn't happen so often. This would mean it's usually covered and plugged but some jolt bump or certain elongation of the spring can cause it to leak out.

Replace and figure it out soon though, as you're only causing more and more damage to your compressor.
kombifan is offline  
Old 12-13-2018, 12:37 AM
  #6  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
Originally Posted by angelglo View Post
you most likely have a leak in your airbags. You are going to have to replace one if not both. depending on your mechanical skills and tools, it can be a job done in your garage for a lot cheaper than the dealer or garage. Also look up arnott for replacements. Also watch there video on replacing the airbag
I had my rear airbags and the compressor replaced last year at the dealer. Now one of my front airbags has taken a hit. This time I plan to replace both front bags on my own. I'm fairly handy with tools. My problem has always been having the right tools. Can you give me a list of tools needed? Socket sizes, wrenches, etc. I already have a ball joint separator on the way per your suggestions in a different thread.

I also have Arnotts on the way.

-Mel
DrMel is offline  
Old 12-13-2018, 02:08 AM
  #7  
Super Member
 
Join Date: Nov 2017
Location: Bethesda, MD
Posts: 582
Thanked 43 Times in 42 Posts
2010 Mercedes GL450; 2000 Mercedes ML55 AMG; 2016 VW GLI SEL Stick!!!
Originally Posted by DrMel View Post
I had my rear airbags and the compressor replaced last year at the dealer. Now one of my front airbags has taken a hit. This time I plan to replace both front bags on my own. I'm fairly handy with tools. My problem has always been having the right tools. Can you give me a list of tools needed? Socket sizes, wrenches, etc. I already have a ball joint separator on the way per your suggestions in a different thread.

I also have Arnotts on the way.

-Mel


I hope you ordered the full unit for the front instead of just the airbags. Youll save yourself plenty of trouble and time is you just do the full shock and air spring unit in one go
kombifan is offline  
Old 12-13-2018, 08:45 AM
  #8  
Super Member
 
Join Date: Jun 2010
Location: San Diego, CA, USA
Posts: 560
Thanked 57 Times in 49 Posts
2007 GL450
Originally Posted by DrMel View Post
This time I plan to replace both front bags on my own. I'm fairly handy with tools. My problem has always been having the right tools. Can you give me a list of tools needed? Socket sizes, wrenches, etc. I already have a ball joint separator on the way per your suggestions in a different thread.
I remember the larger wrenches on the suspension being something like 21 and 23. But you really need to get yourself a full metric combination wrench set. It's way cheaper than buying individual wrenches. Also you need a full set of male Torx / star sockets, and a set of large female Torx. You'll need both of these here, there, everywhere on your truck.

Don't drop the caliper when it's free. Nothing like seeing a caliper dangling on kinked hydraulic lines. I literally got a brake line to later rupture once doing that, though it was a plastic / steel braided line and not the fiber reinforced rubber.

Ignore Arnott's instructions to change the air fitting. You can always change it later if it leaks, and you cause yourself all kinds of possible grief damaging the air line getting the fitting off.

Change your stabilizer links while you're in there. They are a frail part and make mysterious knocking noises on entering driveways, etc. They are cheap and you will have the job half done already anyway.

The one super important tip is to compress the struts and hold them closed with wire or string before putting into position. That is the one part of the job that made me cry for not knowing This One Simple Tip.
eric_in_sd is offline  
Old 12-13-2018, 09:24 AM
  #9  
Super Member
 
Join Date: May 2015
Location: Allentown, PA
Posts: 756
Thanked 43 Times in 42 Posts
'08 GL 320 CDI
Originally Posted by eric_in_sd View Post
The one super important tip is to compress the struts and hold them closed with wire or string before putting into position. That is the one part of the job that made me cry for not knowing This One Simple Tip.
Bingo. I thought of that method about 30 seconds AFTER I struggled with getting both the old one out and the new one in, along with the axle popping out a few times along the way. I finally got it all back together and paused... and thought... This is the exact thought that went through my head: "Wait, couldn't I have just... Idiot".
DennisG01 is offline  
Old 12-13-2018, 03:31 PM
  #10  
Junior Member
 
Join Date: Nov 2016
Posts: 39
Thanked 1 Time in 1 Post
GL450
Originally Posted by DennisG01 View Post
Bingo. I thought of that method about 30 seconds AFTER I struggled with getting both the old one out and the new one in, along with the axle popping out a few times along the way. I finally got it all back together and paused... and thought... This is the exact thought that went through my head: "Wait, couldn't I have just... Idiot".
The one thing I found very easy to work with is ratcheting Tie down to compress the strut. Sorry I should have taken picture when I did mine.
bhuter24 is offline  
The Following User Says Thank You to bhuter24 For This Useful Post:
eric_in_sd (12-22-2018)
Old 12-13-2018, 03:57 PM
  #11  
Super Member
 
Join Date: Jun 2010
Location: San Diego, CA, USA
Posts: 560
Thanked 57 Times in 49 Posts
2007 GL450
Originally Posted by bhuter24 View Post
The one thing I found very easy to work with is ratcheting Tie down to compress the strut. Sorry I should have taken picture when I did mine.
Good suggestion. You connect the two hooks, and then after installation, open the ratchet, pull the free strap end out - it should just slide right through.

The non ratcheting kind doesn't come apart to a free end like that.
eric_in_sd is offline  
Old 12-21-2018, 06:39 PM
  #12  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
Well last weekend I took a stab at replacing the air spring. Thanks to all the tips from you all, I was able to get them installed fairly easy. We've been riding on them for a week now with no issues. No more mornings coming to the truck and seeing a front corner drooping.

I would agrekombifan about replacing the entire unit. Not necessarily because of the time though (taking the old shock off and installing the arnott version was probably the easiest part of it all). In the written instructions it says to check the shocks. If there is excessive leaking, you should replace the whole unit. I'm not sure what symptoms would have shown that leads you to know the shock is busted and needs to be replaced, without taking the air spring off.?

Either way, the shocks were in good working order.

It sure feels good to save so much money on parts and labor!
DrMel is offline  
Old 01-03-2019, 11:16 AM
  #13  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
I have an update.

First, the ride quality of the new Arnott shocks is unbelievable. We took a 2000mi round trip to Disney World last week and the GL rode like a dream. It even seems like the ride height adjusts to/from highway speeds quicker. Before the replacement, you could notice the truck lifting back up after getting off an exit from the interstate. Now it's seamless.

Although the ride is much smoother, I'm noticing a rattling sound that seems to come from the front passenger side of the truck. It's a heavy rattle like the sound you'd hear when the hood isn't latched all the way (I've checked and I wish the problem was that simple).

I did some tests: The rattling sound is not heard at highway speeds when the truck lowers and it's not heard when the truck is raised all the way up. I've rechecked the control arm bolts - everything is impact wrench tight. During the shock replacement, nothing snapped or broke as far as I could tell. The steering works great with no vibrations or knocking. I'm clueless!

Any ideas?

-Mel
DrMel is offline  
Old 01-03-2019, 11:32 AM
  #14  
Super Member
 
Join Date: Jun 2010
Location: San Diego, CA, USA
Posts: 560
Thanked 57 Times in 49 Posts
2007 GL450
Stabilizer links. Much to my chagrin, I got Arnott to replace a strut because a knocking sound appeared shortly after the strut was installed. It turned out that the replacement disturbs the stabilizer links, which don't like their nap interrupted; the strut was fine.
There are multiple possible causes, but the stabilizer links seem to be by far the most common. In addition, they are cheap to buy and cheap to install.
eric_in_sd is offline  
Old 01-03-2019, 01:11 PM
  #15  
Super Member
 
Join Date: May 2015
Location: Allentown, PA
Posts: 756
Thanked 43 Times in 42 Posts
'08 GL 320 CDI
Agree - first, and most likely, culprit are the end links. But I'm not sure I would refer the sound as "rattling" - it's more of a knocking sound. They seem to go bad every few years. Not sure why they can't be made to last longer. Lift the front end, with the weight off the suspension and get your hand on the link - push, pull, HARD, etc - see if you can duplicate. Sometimes it tough to duplicate by hand - until they get really bad. There's not a whole lot of suspension stuff under there - try the push/pull thing with other parts, too.
DennisG01 is offline  
Old 01-03-2019, 02:19 PM
  #16  
Super Member
 
Join Date: Nov 2017
Location: Bethesda, MD
Posts: 582
Thanked 43 Times in 42 Posts
2010 Mercedes GL450; 2000 Mercedes ML55 AMG; 2016 VW GLI SEL Stick!!!
+1 on endlinks. I replaced all 4 recently and it go rid of al my knocking noises and vibration feedback in the steering wheel.

I went for lemforder and rein. Fcp euro 😝
kombifan is offline  
Old 01-03-2019, 05:49 PM
  #17  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
Ok. I can check stabilizer links. The steering wheel does not vibrate though, and neither does the truck.

I attached a video clip from last night as I was driving down my street. In about the first 10 seconds, you can hear the rattle.

-Mel
Attached Files
File Type: wmv
Rattle_1.wmv (1.16 MB, 14 views)
DrMel is offline  
Old 01-03-2019, 06:01 PM
  #18  
Super Member
 
Join Date: May 2015
Location: Allentown, PA
Posts: 756
Thanked 43 Times in 42 Posts
'08 GL 320 CDI
I've personally never heard an end link sound like that - it's the "continuous" rattling (multiple in quick, short succession) that sounds different to me. I suppose if the link was REALLY shot? Either way, get underneath and touch and feel everything.

Didn't leave a tool in there somewhere, did you?

For what it's worth, I've never felt a vibration in the steering wheel when I've had a bad link - but maybe I have just replaced them early enough, before they start acting up that bad. Heck, I think I have a bad one right now - no vibration of any kind - just an annoying knock going over some bumps.
DennisG01 is offline  
Old 01-03-2019, 06:49 PM
  #19  
Super Member
 
Join Date: Jun 2010
Location: San Diego, CA, USA
Posts: 560
Thanked 57 Times in 49 Posts
2007 GL450
Dennis I can feel the knocking in the steering. I'm pretty sensitive, though, having spent most of my miles in cars that need constant attention. It's faint, like a pressure wave finding its way up the steering system.

Mel that's way higher pitched than the knocking I hear from my loose links. Outside the car they're way higher pitched, but inside it's more like thumps from the belly of the beast. I'm baffled; it sounds like lug nuts rattling inside a hubcap. I'm having a hard time imagining what it would be. Something is flailing around down there. On the plus side, that can't be too hard to find; jack it up, or even just lift it on the air springs, and push and pull on stuff.

Heck, fighter pilots go around their birds and wiggle stuff before takeoff.
eric_in_sd is offline  
Old 01-04-2019, 03:48 PM
  #20  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
All tools accounted for.








Stabilizer links look good to me. Shaking things in the wheel well didn't help much - not sure that I can equal the weight of the truck on the road.

Pics attached. While I've got it jacked up, any other thoughts. What does a worn link look like?

Could it be bad ball joints or tie rods?

Last edited by DrMel; 01-04-2019 at 04:11 PM.
DrMel is offline  
Old 01-04-2019, 04:11 PM
  #21  
Super Member
 
Join Date: May 2015
Location: Allentown, PA
Posts: 756
Thanked 43 Times in 42 Posts
'08 GL 320 CDI
Will take a better look at pics later, but a worn link won't "look" bad (unless it's really bad). You gotta (weight off wheel) really push and pull hard - even use a bar to get more leverage on things. Look/listen/feel for any clicking. It won't be as "heavy" sounding as when the vehicle is in use. I'm not saying it IS the links, but that's way to check them 95%. Sometimes it's an educated guess if you can't replicate it.

EDIT: Just adding a quick thought... You said that the rattling ONLY occurs when at normal ride height. Did the sound ACTUALLY go away at highway speeds, or was it just because you may not be able to hear it anymore? When you raise the vehicle, and drive around town, the noise disappears, but when driving the same roads at normal hieght the sound comes back? It's gotta be something in the air spring itself, or the suspension.

Last edited by DennisG01; 01-04-2019 at 06:01 PM.
DennisG01 is offline  
Old 01-04-2019, 06:13 PM
  #22  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
Originally Posted by DennisG01 View Post
Will take a better look at pics later, but a worn link won't "look" bad (unless it's really bad). You gotta (weight off wheel) really push and pull hard - even use a bar to get more leverage on things. Look/listen/feel for any clicking. It won't be as "heavy" sounding as when the vehicle is in use. I'm not saying it IS the links, but that's way to check them 95%. Sometimes it's an educated guess if you can't replicate it.

EDIT: Just adding a quick thought... You said that the rattling ONLY occurs when at normal ride height. Did the sound ACTUALLY go away at highway speeds, or was it just because you may not be able to hear it anymore? When you raise the vehicle, and drive around town, the noise disappears, but when driving the same roads at normal hieght the sound comes back? It's gotta be something in the air spring itself, or the suspension.
There is a chance that I just can't hear it at highway speeds but when it's raised, I know for sure the rattling doesn't exist.
DrMel is offline  
Old 01-05-2019, 06:03 PM
  #23  
Member
 
Join Date: Jan 2017
Location: Houston, TX
Posts: 103
Thanked 15 Times in 12 Posts
Mercedes Benz 2007 GL450 , 2012 BMW 528i and 2002 Chrysler Town and Country (200K+)
It doesn't sound like end links to me.
I would still replace them since they are cheap, even if just to check if that was it. But if you want to be certain, you can disconnect endlinks, drive and check for rattle. A vehicle can be driven with end links disconnected as long as you don't go crazy at curves.
Did you check steering column linkage?
TX07GL450 is offline  
Old 01-05-2019, 06:17 PM
  #24  
Super Member
 
Join Date: Jun 2010
Location: San Diego, CA, USA
Posts: 560
Thanked 57 Times in 49 Posts
2007 GL450
Originally Posted by TX07GL450 View Post
It doesn't sound like end links to me.
I would still replace them since they are cheap, even if just to check if that was it.
Amen and amen.

Originally Posted by TX07GL450 View Post
But if you want to be certain, you can disconnect endlinks, drive and check for rattle. A vehicle can be driven with end links disconnected as long as you don't go crazy at curves.
Few know this. Fine to drive; just don't go hard into a curve. It will oversteer like you won't believe.
eric_in_sd is offline  
Old 01-26-2019, 10:20 PM
  #25  
Junior Member
 
Join Date: Dec 2018
Location: Central Illinois
Posts: 41
Thanks: 0
Thanked 0 Times in 0 Posts
2010 GL 450
I finally had a chance to replace end links. Very quick and easy task.

Unfortunately, the heavy rattle is still there... but at least I won't have to worry about the end links again for a while.

At this point, I'm pretty confident it's coming from the front passenger side.

I'm starting to think it's bushing related, just not sure which ones.
DrMel is offline  

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: GL 450 front suspension mystery


Contact Us About Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: