why is it jerking? tcc silonoid or need filter trans flush?

What is your question?

When at a steady driving rate, I get a slight jerking, and when accelerating (uphill or on the flat) it will jerk more, like it is shifting in and out of overdrive. Goes away when the tranny shift down into 3rd (or a hard accelerating to flooring it). Would replacing to torque converter lockup switch/silonoid fix it? or go with a filter/trans flush?