Abstract: A method of mounting a DEF tank in a recess of a frame of a machine, and such a machine is disclosed. The machine may further comprise a first bracket mounted to the frame, the DEF tank, the fuel tank and a plurality of flexible mediums. The DEF tank is disposed in the recess and may be disposed on top of the first bracket. In an embodiment, the DEF tank is expandable. The fuel tank may be disposed inside the recess. A first portion of the plurality of flexible mediums may be sandwiched between the DEF tank and the frame, and a second portion of the plurality of flexible mediums may be sandwiched between the DEF tank and the fuel tank. Each of the plurality of flexible mediums is configured to constrain the DEF tank from movement that is in excess of expansion of the DEF tank.