An oil tank mounting system for use on a structure of a turbine engine, includes three mounts with each mount configured to constrain the oil tank with a different number of degrees of freedom of movement. A first mount may have fix the oil tank in one degree of freedom, a second mount may fix the oil tank in two degrees of freedom, and a third mount may fix the oil tank in three degrees of freedom. This allows limited rotational and expansion movement while coupling the oil tank to the engine. The mount attachments may be embodied in rubber, with pins, or with spherical joints in a variety of configurations. Frangible pins may be used to absorb energy but still retain the oil tank in the event of a high energy event.