Built from `2002` to `2006`, the `RS6 Avant C5` turns the Audi family estate into a completely excessive autobahn machine. Against a BMW 5 Series Touring or a highly powered Mercedes E-Class estate, it imposed the `V8` biturbo, `quattro` and big-load-space formula very early. On the used market it is one of the most desirable `RS` Audis of its era, but certainly not one of the easiest to restore properly.
Its `4.2 V8 biturbo BCY` works with the `tiptronic`, `quattro` and `DRC`. The real issue is never the brochure, but the long-term quality of follow-up on timing service, cooling, sealing, turbos, gearbox, suspension, brakes and the state of the front end. A minimally maintained `RS6 Avant C5` can still feel impressive; a neglected one quickly turns the mythical fast estate into a very costly mechanical project.