Adjustable-wheelbase vehicle chassis

A chassis (1) of an adjustable-wheelbase vehicle (2) has two side members (5) parallel to the longitudinal axis (4) of the vehicle (2) and having respective front portions (6) and respective rear portions (7) connected telescopically to adjust the distance between a front axle (8) and a rear axle (9); the chassis (1) also has two rear posts (11), the bottom ends (12) of which are hinged to the rear portions (7) of the side members (5) about a horizontal first hinge axis (13) perpendicular to the longitudinal axis (4), and a structure (15) connecting the posts (11) to the front portions (6) of the side members (5); which structure (15) defines a second (16) and third (17) hinge axis, which are parallel to the first hinge axis (13) and extend through the top ends (14) of the posts (11) and through the front ends (6) of the side members (5) respectively.