Originally Posted by asawadude

The newer model features adaptive braking taillights. It has an extra bulb that illuminates under hard braking. Otherwise they are almost identical. If you park an '00-'03 X5 next to an '04-06' X5, you wouldn't see the differences in the taillights unless you were specifically looking for them. The lens of the new light is a little bit of a brighter red and perhaps a little clearer in the clear portion, otherwise they look identical.