An aluminum frame offers a variety of benefits over steel. These include better fuel efficiency because the aluminum frame makes the vehicle lighter in weight, better road handling, better cornering, better crash protection and easier repair.

Although one might think it would be possible to just substitute steel for aluminum, such an action could not be taken because aluminum would have bent at critical weight distribution points. In order for this to work, the Audi team had to change the concept of automotive frame design. Audi patented an aluminum car frame system in 1993 and in 1994 introduced it with a whole aluminum body on the Audi A8.



via Auto Industry