An oil distribution system for an internal combustion engine valvetrain includes a rocker arm base member and a base plate. The rocker arm base member includes a distribution slot disposed into a base lower surface, a plurality of receiving holes extending from a sidewall and/or from the base upper surface of the rocker arm base member into the distribution slot, and a plurality of oil distribution holes passing from the distribution slot through the base upper surface. The base plate being configured to cover at least a portion of the base lower surface including at least a portion of the distribution slot. In operation, the distribution slot receives oil from the plurality of oil receiving holes, passes at least a first portion of the oil to the plurality of oil distribution holes, and the plurality of oil distribution holes discharge at least a second portion of the oil past a base upper surface to provide lubrication to a portion of a rocker arm or other valvetrain components.