W126 560 SEL ball joints... DONE! - PeachParts Mercedes-Benz Forum

LandYaghtLover · #1 12-21-2011, 12:41 PM

What a pain. Since the shop would not do my alignment because the lowers where bad and the fact that I have had replacements sitting on the shelf for almost half a year, I decided to get it done.

There are plenty of write-ups, so I wont go into detail but I have some tips:

As a first timer, I left the hub/rotor assembly attached during removal. It of course must come of, so do it when is on the car. I will give you a little more working room. And this will let you get the splash shield off. In short, make your job easier and remove everything.

One great tip was to remove the tie rod arm. Two bolts hold it to the knuckle. The longer one is forward, shorter towards the back. There is no need to disconnect the tie rod end which can damage the boot. It saves a bunch of time. I read this tip in a thread. Do this first since it will let you maneuver the knuckle around.

The ABS sensor is practically glued in. On the back side there is a bolt holding it in. Just remove it, dont pull on the sensor. I did so on the first one and the "shell" separated! Not a huge deal, I thought. Upon reinstalling it pushed the cap outward. This caused the pick-up to ride against the sensor ring. It wore the tip down a little. I had a noise during the test drive that I suspected was wheel bearings. Maybe over tightened. I soon found the issue. So I recommend just to remove the rear bolt and then tap the the cap inward. Use a socket that is as close to the diameter of the sensor as possible! Anything smaller will dent the soft metal. I used a socket on an extension for better control.

I did not have a bench vise, so removal and installation where a little harder than they should have been. I reinstalled the tie rod arm bolts. This let me hang it on the edge of a wood counter without the ball joint being pounded into the same surface. Below the counter was a wood upright, this kept the top of the knuckle from swinging under the bench. I hope that all makes sense. Then I used a large socket and a big hammer from Harbor Freight to pound the crap out of it. Each time I was ready to give up when by the 6th hit it would finally start to move. Once it starts to come out, it will come out with less effort. Just takes a lot to break the bond.

During install I used a c-clamp compression tool like Autozone rents. One great tip was removing the ball joint boot. This lets you put the open end of the clamp on the ball joint since there is no way an adapter will get in there with the clamp head.

USE LOCK TIGHT. I used it anywhere I could. These weak torque specs MB uses I just dont trust. And this is your suspension, possibly your life!!

You will want to clean out the ball joint seating area! Dont know why, but I did not with the first one and it was a paint to get pressed in. With the second I used a Dremel and a wire cleaning wheel to clean the surface of rust and debris. I then used penetrating oil to clean the surface. Once done, I applied a good amount of penetrating oil again. I VERY carefully applied the same oil to the ball joint seat (remember, the boot is off!!). Once set in place with clamp I put in even more between the two surfaces. This made installing the second one much, much quicker! Depending on the plate you use the ball joint may bottom out. So if you cant get the last mm or so, switch to a large cup adapter or something to make sure it wont hit. My ball joints (Moog) were about a mm deeper than the originals and stuck out a little on the bottom.

Speaking of MOOG. Mine had a the typical seating ring (or whatever you want to call it). Its the just the part that is normally pressed onto when seating and also prevents the ball joint from going right through. The thing to know what that its beveled a little. So even when it is seated, there was the appearance of a gap. It looked like it needed to go in a little further. After much debate with the ball joint and my tools, I found out this was not the case and it was already seated.

Overall it took me about 7 hours to do both. The second only took me 2 hours! And the first took longer because of the ABS sensor issue after the test drive.

Certainly a DIY project, but read up as much as you can and set aside lots of time. I think this about covers it.

LandYaghtLover · #2 12-21-2011, 01:00 PM

Another note I forgot to add. I rented a tie rod separator and a ball joint separator (looks like a tuning fork).

Save yourself some times and use the tie rod separator on the ball joint. If you disconnect the upper control arm the knuckle will move out of the way to get the tool in there. I used the ball joint tool the first time without much issue, but the other side it just would not work. Instead the tips would just hit the wall of the knuckle. After 20 minutes of abuse and trying different angles, I tossed in the tie rod tool and it was out in a minute.

S-Class Guru · #3 12-21-2011, 01:11 PM

Yep, probably the most frustrating thing I ever did on mine. Finally had to drill the old ball joints in several places and collapse the housing to get them to budge. Never could get my Harbor Freight press to fit, so had to have a shop press them in.

DG

LandYaghtLover · #4 12-21-2011, 06:45 PM

If there was a shop, I would have gone that route long ago. But most shops here can not do these and the only one that could wanted $150 just to press out the old and put new in. That would be with me bringing them the knuckles and supplying my own joints!

But its done. Now I have to reseal the SLS pump and then replace the nitrogen accumulators.

pawoSD · #5 12-21-2011, 07:54 PM

When I did them on my 420 I removed the entire spindles from both sides, and had a shop remove and re-install the ball joints into the spindle assembly. Total cost $40.

Total time spent was about 5-6 hours for removal and re-install, but I did all the steering components also.