[thetractorfan]

RCP57 made a very impressive Volvo excavator that was hydraulic. I plan to make one as well. it is best to design on on your own. just draw what you want your RC excavator to look like and then plan out the components. sadly there aren`t many tutorials out there so here is some of the stuff you will need.
pump, valve block, relief valve, return line, tank, oil filter, cylinders, fittings, rubber hoses, 3 hydraulic motors,(if you wanted to have drive and slew done hydraulically), slew bearing, undercarriage, lots of track links, 2 sprockets, 2 idlers, different sized gears for tracks and slew bearing. thats what came off the top of my head. I am really stuck on the electronics though.