This article is aimed at design of a support and a tension mechanism to be mounted on a wheel-tracked chassis of a mine clearing machine. The subject machine serves to detect and disposal mines in terrain. The main advantage of this machine is the possibility to use it from the safe distance thanks a remote control. The wheel-tracked chassis mounted on the machine ensures that the machine is able to overcome extreme obstacles of a terrain. The solved design of the wheel-tracked chassis can be modifying to move using just wheels for better driving properties on metalled roads. Current design of the wheeltracked chassis goes out from the older technical solution, which has been designed for a four-wheeled machine. The latest version of the chassis is designed for a six-wheeled machine. Application of an original structure of the chassis meets problems consisted in formation of cracks in tracks structure therefore the current structure of tracks has to be modified in order to meet all requirements in term of strength and long-term operation. At the same time, two design of a tension mechanism are presented. A tension mechanism is additional device, which will be mounted to the chassis and it will ensure the optimal position of tracks in every load case.