Audi A6 Allroad C5 'Ur-Allroad' (2001-2005)

Launched US 2001 as the 'allroad quattro' (no A6 prefix on the original car), with a 2.7-litre twin-turbo V6 making 250 hp paired with five-speed Tiptronic or six-speed manual; quattro AWD standard. Adaptive air suspension offered four ride heights, from a sport setting (1.5 inches lower than standard) to an off-road setting (2.4 inches higher). For 2003 a 4.2-litre V8 became available, making 300 hp. The C5 Allroad was always a niche car in the US — mid-cycle sales were small — and Audi pulled it from the US after 2005 due to soft demand. Today the 2.7T manual and 4.2 V8 examples are quietly collectible. Air suspension reliability is the biggest concern; many examples have been converted to spring suspension.