Daniel,
hate to tell you this but a Cat 2EC15 is an electric lift, no way it can have a 4G63 engine in it.
you won't get anyone to respond to this until you make a new post with the correct truck model and serial number this engine is in. And unless mitsubitshi remade that engine i never have seen one with a balance shaft in it. If this is true then they did change the engine and this truck is newer than the ones i've worked on, i mean REALLY new and a huge redesign of the engine.