A method for lowering a vehicle chassis to a required vertical position, the vehicle including only two sets of running gear, namely a front set of running gear and a rear set of running gear, each wheel of the sets of running gear being associated with a parking brake, the method including the following successive steps: when the chassis is in its high running position, actuating the parking brake only for all of the wheels of one of the two sets of running gear; lowering the chassis to its low position resting on the ground; and actuating the parking brake for all of the wheels of the other of the two sets of running gear.