When trying to swing the gear with compressed nitrogen, it was apparent that the main landing gear hydraulic cylinder was leaking. After pressurization and retraction, if the cylinder was valved off, the gear legs would slowly fall down. The leak seemed to be around the actuator shaft and not internal leakage around the piston.
Since I had to do the same teardown and seal replacement on the nose gear actuator, I decided to pull the MLG cylinder out and replace all of its seals too.
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