The old Magirus-Deutz firetruck in the beginning is the same as in "Feuertaufe" - it has the same markings ("Wagen 23") and the same plate. However, that firetruck was destroyed in the earlier episode.
When destroyed in the end, the silver Porsche 996 changes into a Porsche 993.
Semir's BMW E46 changes into a BMW E36 when destroyed.