A method of operating a gas turbine engine in a multi-engine aircraft, the gas turbine engine having an engine shaft mounted for rotation in a bearing and a gearbox connected to the engine shaft for torque transmission therebetween, includes axially preloading the bearing using an axially biasing element disposed between the gas turbine engine and the gearbox. The axially biasing element reacts against the gearbox to exert an axial preload force on the bearing and the engine shaft of the gas turbine engine.