Nissan has moved to improve the economic efficiency of its Juke crossover model.

The brand has put both the 1.6-litre petrol and 1.5-litre diesel drivetrains through an “optimisation” programme to reduce emissions and increase fuel economy.

It said that as a result of revised gear ratios, manual derivatives were now cleaner and more efficient.

The 1.6 petrol now returns 47.1mpg on the combined cycle, a claimed improvement of 2.3mpg, and emits 139g/km CO2 – a reduction of 8g/km.

The petrol version now sits in VED Band E, cutting the tax bill by £15. Nissan said once fuel savings were taken into account, the typical owner would save £232 over a three year period.

Fuel economy on the diesel has improved from 55.4mpg to 57.6mpg, according to the manufacturer, with emissions falling from 134g to 129g/km.

The diesel Juke drops a VED Band from E to D as a result of the changes and now costs £95 a year to tax.

Three year savings on the diesel Juke add up to £171.92, Nissan said.

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