For transport of undetachable, oversized and overweight cargos, HUBEI TIANDI and FLJ offer a combination system, Heavy-duty hydraulic modular trailer. This modular system provides almost unlimited possibilities to solve simple as well as complicated transport tasks. The individual platform modules can be combined in longitudinal and lateral direction. It possesses some advantages, such as adjustable platform, load even of axle, little turning radius, easily moving backward, and so on. Adjustable body keeps the horizontal level while running on the upper and lower ramps, and guarantees the running vehicle is smooth-going, steady and safe. Combined hydraulic module trailer is assembled by head girder, module trailers and connection parts for both longitudinal and transverse direction. The framework is consist of flat platform with gridding and single-box-type main girder, the tire is 8.25R15(small type), and is with hydraulic suspension and three-point support, which adopts hydraulic every-wheel steering or controlled steering, dual pipeline brake on every wheel.