Parkers overall rating: 3.5 out of 5 3.5

Miles per pound (mpp) Miles per pound (mpp)

Reliable fuel consumption data for comparison purposes is not available for this model.

Fuel economy

A more stringent standard for fuel economy (WLTP) was introduced from September 2017, and this model was not required to undergo that test. Its fuel economy measured under the previous test system was 26 - 58 mpg. However these figures are less likely to be achievable in real world driving and so should never be compared to another car's mpg which was measured under the newer, more realistic WLTP system.

This is where the M suffers compared to the competition. Basically, Infiniti M runnings costs will be pretty high. There might be a diesel engine but road tax and fuel costs are expensive when compared to the BMW 5-Series and Jaguar XF. However, with so much kit as standard the purchase price of the car is competitive, especially once you’ve started adding the same equipment on the rivals’ equivalent cars.

Infiniti customers might be treated to some of the best customer service on offer but will pay for it with expensive service rates and parts.

Don’t expect to be invited to a Greenpeace picnic any time soon. Infiniti M emissions are high, even for the 3.0-litre V6 diesel engine at 199g/km. While it will average a slightly more respectable 37.7mpg, it's well off the best figures from the big competition.

The M35h petrol-electric hybrid is the cleanest model of the range: tweaks to its drivetrain in 2012 saw its CO2 emissions fall to 159g/km.

Owned by Nissan, Infiniti buyers can expect the same excellent build quality and reliability. Even if any problems do occur you can expect a first-class service from the dealer as the luxury brand prides itself on the excellent one-to-one customer service. There’s also the novel breakdown assistance that covers the driver rather than the car. Infiniti M reliability should be pretty bulletproof.

Ongoing running costs

Road tax (12 months) £125 - £565
See tax rates for all versions
Insurance group 35 - 46
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