My GL550 is getting long in the tooth. 145k with about 30k of it used for towing since I bought it with 105k on it. It feels like the suspension is getting loose though no parts are worn out during inspection. Has anyone proactively replaced ball joints and bushings to firm things up? Am I over thinking it or just trying to come up with an excuse to upgrade?

 

Looking at something like this.

https://www.1aauto.com/mercedes-benz...6854?f=1358439

But thinking I should change tie rod ends too.

 

Well my GL550 must have seen this post. I went to get into it and driver side side front was sagging. It will be getting new struts and bags up front.

 

A sag doesn’t mean you need new struts - just an airbag or two.

Rebuild your front struts using the original ADS struts, don’t trade them in on non-OEM non-ADS struts. Lots of info on this here board wrt this situation.

 

I replaced the front upper and lower control arms and the ball joints on mine in the low 200K range. It definitely got rid of some sloppiness. The ball joints really didn't need replacement, but since I had the parts on hand, I replaced them anyway.

Most of the bushings on mine were visibly cracked, especially the ones on the uppers. If you haven't replaced the rear shocks, I might do that too. Replacing them with a set of Bilsteins got rid of much more of the slop I was feeling than the front end suspension parts.

 

Well I ordered 4 new struts/shocks and front control arms. I already replaced the rear bags, but didn't touch the shocks. Debating on if I just replace the front axles while I am at it. It had click noises when it was sub zero this winter. I have no idea how long they usually last. I am hoping to get another 2+ years out of it. It looks like my BMW M3 will be coming out of hibernation a bit yearly this spring until I get parts and can repair it. (My wife wants to get a new one because they fixed the headrests)

Usually I would get something newer at this point, but the beast still looks great and it does everything I need it to.

It looks like this and in great shape in and out. Actually that ad sold me on getting one.
https://www.kenrockwell.com/mercedes/gl550.htm

 

Ordered axles too.

The wife wants to go drive a x167. (Are they even on lots? Last time we went to MB dealer it the lot was mostly empty)

 

I replaced all of the front end suspension bits and yeah, it made a heck of a difference. Much less slop, no clunking or noises. I would replace your sway bar and steering rack bushings while you're at it since those are likely in rough shape too. Good luck with those upper control arm bolts! Having one arm in the engine bay and the other in the wheel well isn't much fun. You'll need a helper for the driver side rear one at minimum.

 

That is a good idea. I will do those while I am at it.

I am curious about those upper control arm bolts. I just replaced them on my BMW 535 XDrive (F10) when I put coilovers on it. I will have to recruit one of my kids to help. Typically when I do a project like this I get it all sorted and sell it within 6 months. I hope that is not the case this time.

 

Video I am reviewing.

So it here is what I am planning to replace.

-Front Strut/Bags w/ ADS
-Front axles
-Upper and Lower Control Arm
-Swaybar bushings and links
-Tie Rod ends and PS Bushings
-Rear Struts (already changed the bags)
(Not planning to replace ball joints unless they look bad)

 

I know what you mean. I have the same curse

Let me know if you'd like any of the WIS documents!

 

We seen your post re your old ones clicking intermittently. Caution on ordering non-oem parts here - cheap Chinese axles don’t last nearly as long as OEM. If the boots are torn simply replace those and inspect for corrosion. Repack and reseal with new boots.

 

The boots are good. I know what you mean. I put cheap ones in my 535 and then it went bad again within a 6 months.

 

That would be great.

 

Could you post your VIN? I'll get them uploaded a little later today when I get off work.

 

PM sent.

 

All righty here we go. Let me know if I missed any linked documents or anything. For the steering rack bushings, buy new bolts. The bolts are installed in such a fashion that you'll need to move the (I think) front diff to remove them BUT if you loosen the bolts, cut the heads of the bolts off with a hacksaw blade, you can pull the bolt out through the front. When you install the new bolts, just feed them through the opposite way and you'll never have to do that messy work again. It'll save you a bunch of time. I found that info in another thread I'm having trouble finding now. The part number for the bolt is N000000004019.

 

I looked at the PS bushings and they look like new from outside. If I change them I will have to order that bolt.

Honestly most of the bushing look fine outside the ball joints, swaybar endlinks, and upper control arms. It was surprising to me for a 10 year old vehicle with 145k on it.

 

My steering bushings looked just fine on the outside too. If they haven't been replaced yet, I'd bet money they're in need.

 

Gotcha - Two bolts?

 

Yeah but double check me. I remember the driver's side butting up against the diff but the passenger's side might have plenty of space. Also check which side the bolt heads are on. Someone may have already done this. The bolts are 4-5 inches long. The bolts go through the bushings and are what holds the rack in place. Once those bolts are pulled the rack can move around. You may need an alignment afterward.

I remember pulling the blade off my hacksaw and fishing it up next to the bolt head and slowly sawing through it that way.

 

I looked at it last night and you were correct. Passenger side looks like it might come out. The drivers side is very tight. I need to figure out a way to remove those pressed in ball joints.

 

I believe I just flipped the knuckle upside down in the press and pushed it out that way. Dunno if it was the right way to do it, but there you go. You'll need a special socket for getting that stupid huge nut on and off but I want to say I was able to find one at the local O'Reillys. If not FCP should have it.

 

Axle is frozen into the hub. I am trying to get that out with damaging the bearing. Also only one of the front struts arrived on Saturday. I have to pick up the boat on Wednesday and have to get this thing back together. I am not sure my wife wants me towing it with her 2022 X5.

 

I think that’s just the way they are. Both of mine were like that. I used a press like this one. You should be able to rent one at nearly any local parts store.