Abstract: A screw jack assembly (10) for a towed vehicle (100) has a spring housing (30) and a leg section (20) (which may be fitted with a castoring jockey wheel (120) or foot (130) in telescopic relationship, and a compression spring (40) is compressed so that the position of the spring housing (30) relative to weight indicating indicia (20) on the leg section (20) can indicate the tongue weight of the towed vehicle (100). By locking the spring housing (30) and leg section (20) together, a crank shaft (50) can move a main housing (80) relative to the leg section (20) to enable the assembly (60) to raise and lower the vehicle (100) in the manner of a conventional screw jack assembly.