Sometimes loading the stud down with a puller and just letting it sit is helpful. Also, striking the eye of the control arm with medium sized hammer (while the stud is heavily loaded) can also break things loose. The idea is not to beat the stud out of the control arm, but to send a "deforming" shock wave through the eye so that it lets go of the stud. Another variation is to strike the eye on opposite sides at the same with a pair of hammers. Strike the eye perpendicular to the stud. (The idea is to deliver a sharp, ringing blow; not necessarily a hard blow.) Repeated strikes are usually required. And consider the trajectory of parts and tools when things break loose!!!

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