There seems to be some confusion about the loads taken by the suspension bars and by the main gearbox attachment to the airframe structure.
The suspension bars carry the vertical loads. The lift force is transmitted through them to the structure and so they are under tension. In the hangar the weight of the head and gearbox is transmitted through the struts and so they are under compression.
The gearbox is attached to the structure via the barbeque plate which is designed to take up the horizontal forces and not the vertical loads. It picks up the main rotor reaction torque and the longitudinal and transverse loads while damping the vibrations. The fact that it is not designed to transmit vertical forces is obvious from its design. For an example of a main gearbox attachment that is designed to transmit the lift forces look at Sikorsky.
During flight the aircraft is actually hanging from the suspension bars.