Checking ball joints - 560SL
 

I am not exactly sure how to best check the lower ball joints on my SL...I have had for some time an intermittent clunking noise (nothing real serious sounding) and I noticed a few days ago that both of the boots are torn on my lower ball joints (uppers look fine), and so I jacked up the car tonight to take a better look. A friend told me to take a good size pair of channel locks and squeeze the ball joint and control arm - looking for any movement. I definitely have up and down movement - took a pry bar and wedged in and noticed definite movement in the ball joint - maybe 1/8 in, or more??? But very noticeable....

What's acceptable movement? None?

ryan

That is correct. If any doubt, take it to a competent alignment shop and ask for them to check it for you. I just had this done on my 560 and was pleased to find NO MOVEMENT. Simple alignment after tie rods changed and off I went, Straight and true...

torn boots
 

My recommendation is to change the joints if you found torn boots. You probably don't know how long they have been torn. If the joints have not already been worn by road grit, they soon will be.

should be little if any

+1

Just replaced one lower joint on mine due to a clunk when backing up. Jack the wheel up and pull the wheel back and forth at the bottom (not up and down) in different directions. If there is any movement between the ball and receptacle, the joint is loose.

Yea, I've already bought new ball joints (Lemforder's), and am just trying to find time to replace them - along with motor mounts, subframe bushings, and lower control arm bushings...

Can you be a little more specific with how you replaced your lower ball joints?

ryan

You will need a ball joint splitter and a press. Although your 560 arms are slightly different than the one on the pics the process is the same.

You will also need a 14” ¾” all threaded rod, 30mm nuts and a spring compressor plate to secure the mighty front spring to the arm before you remove the steering knuckle.

http://i414.photobucket.com/albums/p...e/dcp_1561.jpg

Internal rod ¾” and compressor plate
http://i414.photobucket.com/albums/p...e/dcp_1551.jpg

30mm nuts and washers
http://i414.photobucket.com/albums/p...e/dcp_1552.jpg

Secure spring
http://i414.photobucket.com/albums/p...e/dcp_1553.jpg

Use ball joint press
http://i414.photobucket.com/albums/p...e/dcp_1555.jpg

Shallow receiver tube
http://i414.photobucket.com/albums/p...e/dcp_1557.jpg

Ball joint out
http://i414.photobucket.com/albums/p...e/dcp_1558.jpg

Pressing in new ball joint
http://i414.photobucket.com/albums/p...e/dcp_1556.jpg

Warning: On no account the bottom nuts of the shock absorber should be removed while the steering knuckle is removed. Your life depends on this!!.

Thanks for the reply - especially the pics and the detailed instructions. In reading through the FSM, little is mentioned of needing any type of spring compressor to remove the springs - the FSM describes an attachment to your jack that keeps it in place on the lower control arm. You jack up the LCA some, remove the lower control arm bushing bolts, slowly lower the LCA and remove the spring. I followed this procedure on my '72 250 (W114 chassis) w/o any problems...

Anyone followed this procedure on the 107?

ryan

Don't mess with springs without a compresor. If one gets away it can cause serious injury/death. I am sure there are shortcuts,but not sure they are wise

This procedure is in the chassis service manual. It requires the use of a specific cradle to do this. A spring compressor would be the way to do if you do not have access to this cradle.

Used the jack method on my car not long ago. Jacked the car fairly high and put a standard jack under the lower arm. I did place a bar down the center of the spring into the center hole in my jack, but don't think that is necessary if you are careful. I actually loosened the bushing bolts, pivoting the arm down and removing the ball joint from the spindle assembly, opposite of the manual. I marked the location of the spring with the arm just to make sure I put it in the same exact orientation as when I took it off. By the time the arm was low enough for the spring to pop out, the spring force was not that great, but still wouldn't put my hands in there. Assembling was a little tricker just to get the spring into position. But once you get it in there and start jacking up the lower arm, the spring is pretty much trapped in place. I did use a second small jack as a back-up while I was clamping the ball joint back into place.

I think do it the way the manual says without the proper special tools would be a pain in the butt and a lot less safe. The way I did it wasn't that bad at all.

KCM,

Let me make sure I got this right...the manual says to remove the lower control arm bushing bolts - leaving the ball joint intact. You then lower then arm slowly using the ball joint as the "hinge" until you can remove the spring...

You did it the opposite way - loosened the LCA bushing bolts and remove the ball joint and used the LCA bushings bolts as the "hinge" - is that correct?

BTW, I am planning on removing the lower control arm and replacing both the ball joint and the LCA bushings - so do you think it really matters which way I do this?? On my W114 250, I did not remove the ball joints - just the eccentric bushing bolts...

ryan

Hi Ryan,

When you supported the LCA to take out the bolts, did you having anything on the jack to stabilize or otherwise control it? Where did you position the jack?

I need to do this on three W115/107 cars and am nervous of the spring getting out of control...

D.

spring outa control = serious injury, be careful, why not just get a spring compressor?

I have done one side as of today - taking my time!

Did not use a spring compressor...I attached some of that carpet pad stuff - folded up - to the jack, just to keep the jack from slipping as I was trying to avoid metal to metal contact (jack to LCA)...I'm sure anything like leather or a piece of carpet, etc. would work... The trick is to make sure the jack won't slide - not just the jack to LCA, but also the wheels of the jack on our garage floor!

Again, I have studied the FSM numerous times and did this earlier on my W114 without incident. The FSM does NOT call for a spring compressor...but I'm sure you could probably figure out a way to better attach the jack to the LCA if you are nervous.

I jacked up the control arm some and removed the LCA bushing eccentric bolts (I had already removed the lower shock absorber nuts and the sway bar bushing). I positioned the jack directly underneath the hole in the LCA and with the jack lever pointing just to the rear of the front wheel - and I actually reinstalled the tire and lowered the jack from behind the tire. No real problems - lowered the jack slowly, making sure nothing was sliding around, and removed the spring. You might hear a noise when the LCA bushings break loose and the arm starts to lower... and I would mark the position of the spring with some spray paint to get it reinstalled in the same place...

Removing the spring was actually the easiest part of the job - I had all kinds of trouble getting enough clearance to remove the ball joint from around the dust shield! Had to remove the steering knuckle and take everything off and to my bench...On the driver's side, I am going to try and figure out another way to get the ball joint enough clearance - probably will just try and bend the dust shield enough.

I'm not "recommending" this procedure - just describing how I did it. I have also discussed this procedure with several local Mercedes mechanics and none indicated that a spring compressor was necessary either - and one gave me the carpet pad/leather/vinyl idea...

I'll post again once I'm done - also replacing the subframe and motor mounts at the same time.

ryan