A fixed or adjustable motorized container carrier for transporting a shipping container on a suspended overhead track having a first rail and a second rail, where said first rail and said second rail are spaced apart, parallel, and extend longitudinally along the suspended overhead track, the fixed or adjustable motorized container carrier comprising: (a) a first trolley assembly and a second trolley assembly (110 or 310) able to be mounted on said first rail and said second rail, each of said first trolley assembly and said second trolley assembly comprising: (i) a support frame structure having a first section comprising a first interior frame spaced apart from a first exterior frame, a second section comprising a second interior frame spaced apart from a second exterior frame, and a crossbeam (113 or 313) interconnecting said first and second sections; (ii) a first pair of load wheels and second pair of load wheels (115 or 315) engaging said first rail and said second rail, respectively, said first pair of load wheels mounted and extending laterally inwardly within said first section of said support frame structure, said second pair of load wheels mounted and extending laterally inwardly within said second section of said support frame structure; (iii) first and second motor/gearbox sets (112, 114 or 312, 314) mounted on said support frame structure, said first and second motor/gearbox sets when actuated inducing rotation of said first pair of load wheels and said second pair of load wheels along said first rail and said second rail, respectively; and (iv) a rotatable coupling (116 or 316) extending downwardly from said crossbeam; and (b) a carrier body (130 or 330) comprising (i) a first bumper and a second bumper (140, 145 or 340) extending longitudinally outwardly from oppositely disposed outer ends of said carrier body (130 or 330); wherein said carrier body is suspended from each trolley assembly by said rotatable coupling. (a) a first trolley assembly and a second trolley assembly (110 or 310) able to be mounted on said first rail and said second rail, each of said first trolley assembly and said second trolley assembly comprising: (i) a support frame structure having a first section comprising a first interior frame spaced apart from a first exterior frame, a second section comprising a second interior frame spaced apart from a second exterior frame, and a crossbeam (113 or 313) interconnecting said first and second sections; (ii) a first pair of load wheels and second pair of load wheels (115 or 315) engaging said first rail and said second rail, respectively, said first pair of load wheels mounted and extending laterally inwardly within said first section of said support frame structure, said second pair of load wheels mounted and extending laterally inwardly within said second section of said support frame structure; (iii) first and second motor/gearbox sets (112, 114 or 312, 314) mounted on said support frame structure, said first and second motor/gearbox sets when actuated inducing rotation of said first pair of load wheels and said second pair of load wheels along said first rail and said second rail, respectively; and (iv) a rotatable coupling (116 or 316) extending downwardly from said crossbeam; and (i) a support frame structure having a first section comprising a first interior frame spaced apart from a first exterior frame, a second section comprising a second interior frame spaced apart from a second exterior frame, and a crossbeam (113 or 313) interconnecting said first and second sections; (ii) a first pair of load wheels and second pair of load wheels (115 or 315) engaging said first rail and said second rail, respectively, said first pair of load wheels mounted and extending laterally inwardly within said first section of said support frame structure, said second pair of load wheels mounted and extending laterally inwardly within said second section of said support frame structure; (iii) first and second motor/gearbox sets (112, 114 or 312, 314) mounted on said support frame structure, said first and second motor/gearbox sets when actuated inducing rotation of said first pair of load wheels and said second pair of load wheels along said first rail and said second rail, respectively; and (iv) a rotatable coupling (116 or 316) extending downwardly from said crossbeam; and (b) a carrier body (130 or 330) comprising (i) a first bumper and a second bumper (140, 145 or 340) extending longitudinally outwardly from oppositely disposed outer ends of said carrier body (130 or 330); wherein said carrier body is suspended from each trolley assembly by said rotatable coupling. (i) a first bumper and a second bumper (140, 145 or 340) extending longitudinally outwardly from oppositely disposed outer ends of said carrier body (130 or 330);