Key among the modifications brought to the popular executive class saloon and estate is a new-generation turbocharged 2.0-litre four-cylinder diesel engine that is claimed to provide improvements to performance, fuel economy and CO2 emissions.
The B47 designated unit, first unveiled in the facelifted BMW X3, uses the latest common rail injector technology, endowing the reworked 518d with 148bhp and 295lb ft of torque – an increase of 7bhp and 15lb ft on the existing model.
The 520d’s reserves have been boosted by 6bhp to 187bhp, with torque increasing by a similar 15lb ft to the same 295lb ft as the 518d.
Allied to the new engine is a reworked version of BMW’s eight-speed automatic gearbox, which is claimed to bring further fuel savings.
A six-speed manual remains standard on both models. BMW’s official performance claims give the 518d and 520d saloon respective 0-62mph times of 9.5sec and 7.9sec in combination with the optional automatic gearbox, with the 518d and 520d Touring put at 9.9sec and 8.1sec.