My mechanic called them brake force guide rod bushings. They were at the rear end of the rods that run somewhat perpendicular with the car's frame on the front suspension and connect with the lower control arm. I did mine myself on my W126 and can tell you it is a pain with everything else still in place. If the springs were out, it would be easier as everything wouldn't be under load.
If you do it yourself, make sure to measure the total length of the rod to where it meets the mount for the bushing, as the bushing's threaded coupling was a slightly different length on the replacement parts I got.