The Audi R8 V12 TDI (later renamed the Audi R8 TDI Le Mans),[1] was a diesel-engined concept car[2] that was first presented to the public at the 2008 North American International Auto Show on 13 January[3] and then the Geneva Motor Show in March in the same year.

The car was fitted with a 6.0-litre V12 engine, utilising Volkswagen Group's long-established Turbocharged Direct Injection (TDI) turbodiesel technology.

The car utilises Audi's quattro permanent four-wheel drive system and a 6-speed manual transmission.

The V12 TDI requires more cooling than the standard R8, hence a NACA duct is incorporated in the roof to feed additional air into the engine.

In May 2009, Audi decided to halt plans for possible production of the R8 TDI, citing "the cost of re-engineering the petrol R8 to accommodate the massive twin-turbocharged diesel engine is simply too great – and that it would be unable to recoup its investment through sales alone".