Ball Joint Failure

[Matsalleh76]

Two nights ago, driving home in a very heavy rain I turned into my driveway and BANG the left front suspension collapsed. It was really pissing rain and of course I had no umbrella.....the car was basically on the ground with the left front tire pressed up against the upper inside of the mudguard and the control arm resting on the ground.

Kind of hard to drive like that so I abandoned the car and walked home; luckily only 100 meters. Had the car towed in the next morning.

The ball joint failed. The pin portion of the ball had sheared cleanly off.

Have a look at the attached photo. Note the wear/hammer marks around the socket and the smooth end of the pin. Disregard the vise grip marks on the pin: had to use a vise grip to pull it from the spindle.

Studying at the broken pieces it appears that the pin may have actually sheared "???" minutes, hours, or days (!!) before it let loose but the weight of the car kept it in place in the ball joint body/socket until just the right steering angle and loading allowed it to pop out. While it was still in the socket it banged around and hammered the rim of the socket.

Thinking back a few days I remember a strange momentary feeling in the steering while cornering at speed: like something was slightly loose. It did not happen again so I disregarded it. I think the car was trying to tell me something.

I did a search on the 190 Forums and found that this is not an unusual occurrence. There are references to numerous ball joint failures but all seem to be due to the joint wearing out and the entire ball and pin pulling out of the worn out socket leaving an empty socket in the control arm. All also seem to be preceded by some indication of problems: squeaks & groans or vague steering.

I have never heard or found references to the pin shearing and I can only assume that it is due to a manufacturing fault in the no-name ball joints I installed.

Driving with worn-out ball joints is irresponsible and dumb. Having a worn out joint separate at a school crossing could be disastrous. But having an un-worn joint shear with (maybe) no warning is frightening as the result is the same: at anything above driveway speed = total loss of directional control.

The moral of the story:

1) do not buy cheap e-Bay no-name ball joints (they were installed only 14 months ago)
2) whenever you have the car on a lift stick a big screw drive between the control arm and the spindle and see if you can get them to move.
3) if your steering does anything funny investigate immediately

The lower control arm was not damaged so installed two MERCEDES ball joints and consider myself very lucky.

I am interested in other's ideas/comments on this but am not really interested in hearing from those who have had worn-out joints fail. Sorry, but they should have been replaced before they failed.

Has anyone else suffered a sheared ball joint pin failure? If so do you know the source of the failed component? Any forewarning?

Most curious,

[Rouven036]

the reason is like you have discovered ,the cheap shit ball joints.maybe mercedes parts are not as cheap as these you have used , but there is a reason for the higher price.
axle-,suspension-,brake-,steering parts etc. are safetyparts and you should never ever save money on this place because your life and the life others could hang on it.
of course when your ball joints are worn out,there is often an squeaking and groaning noises while turning the steeringwheel.if you ignore it a while it could be that the pin would be pulled out of the socket when the steering is in full angle.
if you use parts with higher quality and mount them correctly , then the liftime of the ball joints will be 100tkm or longer,debends also on the roads.
i think,if you check the ball joints every 20tkm it would be enough.there is also a special tool from mercedes available to measure the ball joints when the care is standing on the wheels.