Based on VW's proven 2.5 TDI, it has a new fuel-injection system, turbo and cylinder head, as well as a remapped ECU. The result is a much cleaner and more efficient motor, with the added benefit of a 5bhp power increase and an extra 40Nm of torque.
We drove a top-of-the-range Elegance, which comes with standard automatic transmission - the best combination, as the V6 is well suited to the self-shifter, offering plenty of power and impressive refinement. The lesser Comfort models get a six-speed manual, which has a notchy change and is nowhere near as smooth to drive. But the auto is much dirtier, giving out 213g/km of CO2 compared to the six-speeder's 192g/km. Removing a costly company car tax levy over the outgoing V6 TDI has helped reduce liability from 31 to 27 per cent, yet the model remains four tax brackets higher than a manual model, and a whole six groups above the Mercedes C220 CDI.
That's a shame, because the newcomer is a fine car. The 2.5 TDI Superb might be as good as its name suggests, but the sensible money is on the cheaper four-cylinder 1.9 TDI 130.
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