Is it possible to get some lubricant into the lower ball joint on a 98 C230?
 

The car is making a groaning noise in the front when the steering wheel is turned. Steering fluid is topped up. Noise seems to be coming from the lower front control arm area on both sides. The rubber thing that usuaslly has the grease in it THAT IS IN BETWEEN THE BALL JOINT AND THE CONTROL ARM IS FLAT AS A PANCAKE. Sorry had the caps on. I can't seem to peel back the rubber to get anything in there. I thiought i would try to get some lube in there to see if I could diagnose the noise.

How to inject grease into ball joints
 

A good auto parts store will have a 'grease injector' fitting--a hypodermiuc needle (big one!) with a grease zerk fitting on the end. It is used to lube 'sealed' bearings and other tight spots. Easy to punch a hloe in the joint boot (it reseals as soon as you pull the needle out) and pump in 4-6 shots of moly-sulfide grease. It helps lubrication to take the load off the joint by placing a jack under the control arm between the spring and ball joint.

Not a high probability of a permanent fix. The joints don't usually dry out and if they get scored they will wear rapidly.

I 've never heard of this. I figured i could have pierced the boot and injected some grease but then there is a hole that water dirt and salt can get into. I don't get how a zirk fitting can just rest in the rubber. If I were to try and put more grease in at a later time wouldn't it just push the fitting into the boot and then I would definitely have a whole in the boot. How does the fitting stay attached to the boot?

greasisng sealed ball joints
 

You were given correct instructions but you are on the wrong track! There is no zerk fitting in a sealed joint. The grease needle is the only way to inject grease into a sealed ball joint. Again as a spreviously stated this is no guarantee that joint will be protected against dirt, oil, water, etc. At most a temp solution. Good luck, AbeG

The zerk fitting is on the needle and comes out when you pull the needle out. The hole made by the needle is so small (no material is removed) that it effectively seals up as soon as the needle is withdrawn.

Wholey zirk!!