Work designing cylinder heads for Ford although not a CAD designer have experience with a number of systems,

For design learn CATIA V5, if needed Solidworks (both made by DS)

Once you learn how to model / surface you can use most systems by just learning where the buttons are.

AutoCAD is good to know although mainly used in the 2D format for layouts etc in the automotive industry.

Most 3D modelers can handle STEP or IGES formats.