In response to the likes of Volkswagen and Renault, which offer six-speed manuals in their diesel saloons, Ford linked up with transmission expert Getrag to develop the gearbox. It's the first product of their joint venture and will spawn a new family of Ford transmissions over the next few years.
The box was designed to be used with a front-wheel-drive diesel car, which means it's strong enough to cope with high levels of torque. But is the unit really a significant improvement over the previous five-speed system?
Well, it certainly has its benefits. The tall sixth gear boosts fuel economy on motorways, where the Mondeo averages 55mpg. What's more, that extra cog means lower gearing across all the ratios, giving the car a sportier edge. 0-60mph takes only 9.8 seconds, the same as the Mondeo 2.0-litre petrol.
You'd be forgiven for thinking the six-speeder is the perfect companion for the TDCi engine, but it's not without compromises. Despite better economy and flexibility, it reduces the Ford's driver appeal. Whereas the five-speed model enjoyed a firm, positive shift action, the newcomer's transmission feels springy and notchy. The six-speed Mondeo might seem a better car on paper, but on the road it falls a little short.
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