A motor assembly with an integrated cooling system, comprising: a stator contained within a motor enclosure; a rotor shaft, wherein said rotor shaft passes between a first end cap and a second end cap of said motor enclosure; a rotor mounted to said rotor shaft, wherein said rotor shaft includes a hollow region; a coolant pump for injecting a coolant into said motor assembly; a coolant reservoir in fluid communication with said coolant pump; a second coolant passageway, wherein said second coolant passageway fluidly couples a region within said motor enclosure to said coolant reservoir, and wherein said coolant within said region of said motor enclosure flows into said coolant reservoir via said second coolant passageway; and a plurality of distribution thru-holes integrated into said rotor shaft, wherein each of said plurality of distribution thru-holes fluidly couples said hollow region of said rotor shaft to said region within said motor enclosure, wherein said coolant passing from said hollow region to said region within said motor enclosure directly contacts said stator and said rotor prior to flowing through said second passageway into said coolant reservoir. characterized in that the assembly further comprises a first coolant passageway, wherein said first coolant passageway is integral to said first end cap, wherein said first coolant passageway fluidly couples said coolant pump to said hollow region of said rotor shaft, wherein said first coolant passageway further comprises an output aperture located within a bore of said first end cap and adjacent to said rotor shaft, wherein said rotor shaft includes at least one intake thru-hole, wherein said coolant flowing through said first coolant passageway and through said output aperture is injected by said coolant pump into said hollow region of said rotor via said at least one intake thru-hole; and a first seal and a second seal, wherein said first seal and said second seal confines said coolant passing through said first coolant passageway and through said output aperture within a region defined by said rotor shaft, said bore of said first end cap, said first seal and said second seal. a stator contained within a motor enclosure; a rotor shaft, wherein said rotor shaft passes between a first end cap and a second end cap of said motor enclosure; a rotor mounted to said rotor shaft, wherein said rotor shaft includes a hollow region; a coolant pump for injecting a coolant into said motor assembly; a coolant reservoir in fluid communication with said coolant pump; a second coolant passageway, wherein said second coolant passageway fluidly couples a region within said motor enclosure to said coolant reservoir, and wherein said coolant within said region of said motor enclosure flows into said coolant reservoir via said second coolant passageway; and a plurality of distribution thru-holes integrated into said rotor shaft, wherein each of said plurality of distribution thru-holes fluidly couples said hollow region of said rotor shaft to said region within said motor enclosure, wherein said coolant passing from said hollow region to said region within said motor enclosure directly contacts said stator and said rotor prior to flowing through said second passageway into said coolant reservoir. characterized in that the assembly further comprises a first coolant passageway, wherein said first coolant passageway is integral to said first end cap, wherein said first coolant passageway fluidly couples said coolant pump to said hollow region of said rotor shaft, wherein said first coolant passageway further comprises an output aperture located within a bore of said first end cap and adjacent to said rotor shaft, wherein said rotor shaft includes at least one intake thru-hole, wherein said coolant flowing through said first coolant passageway and through said output aperture is injected by said coolant pump into said hollow region of said rotor via said at least one intake thru-hole; and a first seal and a second seal, wherein said first seal and said second seal confines said coolant passing through said first coolant passageway and through said output aperture within a region defined by said rotor shaft, said bore of said first end cap, said first seal and said second seal.