According to edmunds, all A4 models receive minor updates to the interior, exterior and chassis. The front styling has been changed with new headlights, a new grille, new door handles and new mirror housings. Inside, you'll find a revised instrument cluster and center console, along with other minor interior changes. The rear seats have been modified to improve comfort. There are now optional head airbags and xenon headlights. The chassis has been reworked for improved ride comfort and responsiveness.
Audi's A4 is sleek, sophisticated, speedy and has won praise from the worldwide automotive media. Small and safe, the A4 has scored well in government crash testing. For U.S. buyers, this translates into a competent alternative to the BMW 3 Series, the Acura TL and the Volvo S40/V40, among others.
2000 Audi A4 Owners Manual