Independent, Expert EV Reviews & Advice Since 2006

Road Test of the Infiniti M35h


Performance, luxury, efficiency and individual design; these are descriptions that are used in the marketing of many cars, but is the Infiniti M35h actually the first car that genuinely deserves all these titles?

Infiniti M35h Road Test

Model/Engine size : M35h
: Petrol-electric hybrid
Fuel economy combined : 40.4 mpg
Green Car Guide rating : 9/10

To find out if such a collection of superlatives should be applied to this vehicle, we decided to test the car with a journey from the Cholmondeley Pageant of Power venue in Cheshire to the Goodwood Festival of Speed near Chichester – and back again. Would the petrol-electric hybrid come close to achieving the official 40.4 mpg? Would it provide the refined level of high-speed cruising that you should expect from a car of this class? With 359 bhp, would it be able to quickly escape from the crowds pouring out of the Goodwood car park?


o the test (one of the very first drives of the M35h on public roads in the UK) began around the Pageant of Power circuit in Cheshire. Even before arrival at the start line, you’re struck with the refinement of the car. Because it’s a hybrid, at low speeds the car can operate in electric mode, courtesy of its motor and battery. In this mode the car is virtually silent.

When it comes to acceleration, with a 0-62 mph time of just 5.5 seconds, progress from the Pageant of Power start line is rapid. The M35h has an automated 7-speed transmission, with four driving modes: normal, sport, eco, and snow. Sport mode was selected for the circuit and thanks to the combination of the 3.5-litre V6 petrol engine and electric motor, the M35h just takes off and keeps going. There’s no rise and fall of power as would be the case if you climbed through the revs in each gear in a petrol car with manual transmission, just continuous, effortless power delivery.


Perhaps one of the most significant things about this car from our point of view is that it doesn’t share the sensation of its revs rising sky-high under acceleration that is so common with most hybrids that have a CVT transmission. Instead, there is a completely direct feeling from the powertrain in response to the input on the accelerator pedal. Appropriately, Infiniti calls its technology a ‘Direct Response Hybrid system’. This combines the petrol engine with a powerful 67 bhp electric motor, supported by a 1.3 kWh laminated lithium ion battery pack, and the system uses two clutches. The first allows the petrol engine to be declutched when the electric motor is in use, increasing electric efficiency, whilst the second replaces a torque convertor, making the 7-speed gearbox into an automated manual. This means that you can change gear manually (without a clutch) if your prefer.

The 67 bhp electric motor plays a significant role in the excellent fuel consumption figures, as it is powerful enough to propel the M35h at up to 62 mph, dramatically increasing electric use. This, combined with a lower kerb weight than the diesel model and a very slippery drag coefficient of 0.26, adds up to big fuel savings. You do have to sacrifice some boot space to accommodate the batteries, but, crucially, it still fits four golf bags.

The Infiniti M35h on its road test

But it’s not just the hybrid system that works well. Approaching the first corner at Cholmondeley, the brakes prove that they’re easily up to the task of stopping the large five-seater saloon – and of course they also recover energy that would otherwise be lost. The steering is also well-weighted, with surprising amounts of feel for such a refined car.

Once you’re into the corner, despite the M35h being a relatively heavy car, it corners extremely competently. At this point you’re thankful that Infiniti has engineered the vehicle to be rear-wheel drive, as you can push the car around the corner with the throttle, rather than expecting the front end to ultimately go wide if you were in a front-wheel drive machine.


Accelerating out of the two corners and up the long back straight, there’s the continuous surge of smooth power from the V6 and the electric motor. The speed keeps climbing very quickly until the next set of off-camber corners, crests and dips. The body control of the M35h takes all of this in its stride, showing that this is certainly no ordinary executive saloon, but one that has been designed with performance in mind.

In no time at all I’m over the finishing line and it’s time to head down to Goodwood, so I switch the drive mode to ‘eco’ to see how many miles we can extract per gallon over the 250 miles of roads in front of us. This route consists largely of motorways, but also A-roads and dual carriageways. Once out on the open road, it doesn’t take long to realise that the M35h has an excellent ride, and that it is extremely quiet at all speeds.


There’s plenty of electronic adjustment for the seat and the steering wheel, making it easy to get a comfortable driving position, which can then be fine-tuned as required. With around four hours on the road, there’s time to examine the Infiniti’s interior. Overall, this is a very aesthetically-pleasing environment. Compared to some other cars in this class, there is an abundance of curves and creative design touches. For instance, the flowing insets in the door trims are said to be influenced by Japanese calligraphy.

The quality of all materials is excellent, and care has been taken to ensure that the controls switch on and off with a particularly upmarket feel. There are a number of interesting features, including numerous safety systems, heated and ‘air conditioned’ front seats, and ‘Forest Air’, a special form of naturally-inspired ventilation which is said to aid alertness when driving. This sounds a bit far-fetched, but perhaps it worked, as 250 miles later, I arrived at Goodwood feeling as fresh as the moment I stepped into the car.


And so, the key question – had the car achieved 40.4 mpg? Well, very nearly – it averaged 39.5 mpg – and the route was driven at normal speeds, mostly around 70 mph on motorways. I am convinced that it would have been easy to exceed 40.4 mpg if it had been a concerted eco-driving exercise.

So 39.5 mpg is impressive for fast motorway driving in a luxury performance saloon with 359 bhp on tap. This figure was definitely helped by the ability of the car to go into electric mode when coasting at much higher speeds than other hybrids. You can observe this yourself by watching the EV light illuminate on the dashboard when lifting off the throttle on the motorway.


The M35h also has another trick up its sleeve. In eco mode, when you accelerate, the accelerator pedal pushes back up against your foot. This so-called ‘eco pedal’ feels strange, and being the first time it’s ever featured on a car, I’m sure it won’t meet with universal approval. But the idea is to regulate the instincts of your right foot, and Infiniti claims that this innovation can improve fuel consumption by up to 10%.

So how does the Infiniti compare with rivals? In terms of petrol executive cars that come closest to the Infiniti’s fuel consumption, there’s the Mercedes-Benz E200, which can manage 38.7 mpg, and the BMW 5 Series 523i SE, which averages 37.2 mpg. However if you then compare the power of these executive eco-warriors, the Mercedes can only muster 184 bhp, and the BMW only does slightly better with 204 bhp, which all seems rather weedy against the M35h’s 359 bhp.


Admittedly, the M35h is considerably more expensive than these particular cars, at £46,840. This sounds like a lot of money, but actually the M35h is better value than it may appear. When specification and performance are taken into account it is on a par with diesel rivals, whilst the lower company car tax liability of just 21% will bring big savings. And unlike some other brands, the extra premium for the hybrid model over the petrol and the diesel M models is relatively small. Over an equivalently specified M30d, the hybrid costs just £1200 more.

However, as impressive as any of the above statistics may be, there may be one other major benefit of the Infiniti: it’s not German. Have you seen the average corporate car park recently? The chances are that it looks very much like the car park at BMW or Mercedes headquarters. Is there anyone out there who’s in the market for an executive car who feels they would like something a little different to reflect their unique personality? If so, they should consider Infiniti.


Although Infiniti has had a presence in the American market for over 20 years, it is a relatively new brand in the UK. Infiniti has a relationship with Nissan in a similar way that Lexus has a relationship with Toyota. However Infiniti is determined to be seen as more than a Lexus. The brand has very strong core values built around the very best elements of Japanese tradition and way of life, and this encompasses many areas ranging from quality standards to design influences. There are increasing amounts of niche vehicles out there – now there is a genuine alternative to German luxury performance machinery for people who want a genuinely different and interesting option.

Infiniti is also committed to offering the very best possible levels of customer service. At the moment, it will be doing this with very few Infiniti Centres. This handful of dealerships is set to grow over the coming years, however in the likely absence of a dealer near you for the foreseeable future, the Infiniti website is your first port of call, where you can specify your desired car down to the smallest details.


Summary and Review of the Infiniti M35h

In answer to our original question, yes, the Infiniti M35h does have it all, with its luxurious interior, individual curvy design, and eco mode and sport mode effectively giving you two cars – an efficient cruiser and a high performance (and great sounding) sports saloon . So surely it deserves a Green Car Guide rating of 10 out of 10? Well, it probably wins the award for the car that comes closest to getting 10 out of 10, but just falls short – on a technicality.

It may sound very trivial, but we would like to see the Infiniti M35h with emissions of 159 g/km CO2 rather than 162 g/km. Virtually all manufacturers with cars in this emissions ball-park do whatever they can to magically sneak under the 160 g/km CO2 barrier. This is a key threshold in the UK for company car tax, but it’s obviously not as significant an issue in Japan.

And although we’ve agreed that the M35h represents good value for money compared to rivals, we have to acknowledge that the car is unfortunately not particularly affordable for the majority of people.

So it’s for these admittedly fairly trivial reasons that, although our heart wants to give the car a (very rare) 10 out of 10, our head says it gets 9 out of 10. If Infiniti can find a way to give us lower emissions and higher fuel economy for no extra cost we’ll be more than happy to take a revised model back down to Goodwood next year for another test.

In the meantime the Infiniti M35h represents a genuine step-change in the way a hybrid car drives, and the Infiniti brand should be of real interest to driving enthusiasts who want performance and greater efficiency.

Paul Clarke

Paul Clarke of Green Car Guide

Car details and fuel economy figures

Fuel economy extra urban: TBC
Fuel economy urban: TBC
CO2 emissions: 162 g/km

Green rating: VED band G – £155

Weight: 1830 Kg

Company car tax liability (2011/12): 21%

Price: £46,840 (From £38,540 to £47,680)

Insurance group: TBC

Power: 302 bhp (petrol) 67 bhp (electric) system 359 bhp

Max speed: 155 mph

0-62mph: 5.5 seconds

Rear view of the boot of the Infiniti M35h