Conventional wisdom says that if you are wafting along in a large, luxurious sedan then it should be this quiet, the same conventional wisdom says that if it’s a diesel then it probably won’t be this quiet.
What is more I’d swear that the BMW 740i that I was driving a few days before had more mechanical, induction, engine noise than does this 730d sibling!
The first diesel powered 7 Series to be offered by BMW in Australia makes a strong argument, through its clean, powerful and frugal performance, to persuade even well heeled purchasers that there is a case for taking the diesel option.
Back in Europe just about every BMW, indeed every car, has a diesel badge on the back, and BMW has been a leader in the technology development, but here in Australia the German company only introduced its first diesel model five years ago.
In the intervening time diesels have risen to become one-third of local sales across the model range and now even the most prestigious BMW buyer has the option of making that choice, perhaps not driven by a innate desire to save money but rather to be seen to be ‘green’.
It’s interesting to note, however, that a 730d owner will save money anyway as the diesel powered car is actually priced at $198,800, some $4200 cheaper than the identically specified 740i, which uses a twin-turbo petrol engine.
What BMW believes will appeal more strongly to the 7 Series buyer is the fact that the 3.0-litre, turbo-diesel engine underscores all its major rivals on fuel consumption and emissions outputs.
The 730d engine generates 180kW of power at 4000rpm and 540Nm of torque between 1750-3000rpm. As a result, the BMW 730d accelerates from 0-100km/h in 7.2 seconds, yet uses just 7.2L/100km of fuel and emits only 192g/km of CO2, making it the most economical car in its class.
It also means the 730d is the first car in the upper luxury sedan segment to emit less than 200 grams of CO2 per kilometre, by comparison the Lexus LS600hL, despite being hybrid powered, emits 219g/km, and consumes 9.3L/100km of petrol.
The new 3.0-litre, turbo-diesel, six-cylinder engine delivers performance akin to a V8 engine, but with the fuel economy of some four-cylinder engines housed in much smaller bodies.
Like all of the 7 Series models the BMW 730d is mated to a six-speed automatic transmission equipped with optimised gearshift dynamics that make for faster shifting, improved shift comfort and reduced fuel consumption.
There’s not a hint of all this frugal-ness on the road as the 730d delivers uncompromising performance and bursts into life without the slightest hint of a rattle or a wheeze, so typical of diesel engines from other manufacturers.
In fact, had somebody not spent an hour telling me how good this diesel engine was, and had I not already noted the ‘d’ badge on the rear, I’d have been more inclined to believe we were driving something with V8 power, once on the road.
Perhaps the only give away would be the tinge of turbo-lag that is evident on initial acceleration, but once underway there is abundant performance thanks to that massive torque figure and even on twisty country roads this very big, heavy car feels more like a sports car as it hauls itself out of corners.
That acceleration is so linear and progressive you can well believe the tales of those who have travelled on autobahns in this car and cruised for hundreds of kilometres, fully laden, with the speedo needle sitting steadily on 200km/h.
While we never saw figures even remotely approaching that, some spirited driving through the country lanes around Bowral in New South Wales saw the trip computer tell a ‘woeful tale’ of fuel consumption nudging 8.0L/100km, a figure Holden Caprice drivers can only dream of.
For the most part we actually recorded 5.8L/100km while cruising on the motorways and this generally nudged up into the region of 7.5L/100km when giving the throttle some vigorous use through the twisty bits.
While doing just that we observed that the steering weights-up nicely, although it can feel a bit remote mid-corner, and despite the alloy engine block the rear-wheel-drive 730d does get a bit nose-heavy under directional changes.
We can’t generally disagree with BMW’s claim that the all-new suspension optimises ride and handling with a particular accent on comfort.
The ambience inside the car is one of relatively serene quiet, there’s just no real noise from the engine, the run-flat tyres or the wind. Comfort is typical of the 7 Series although we are inclined to the view that taller rear seat passengers are a little cramped for legroom, when similar height people occupy the front seats.
Boot space is the same as other 7 Series and is adequate for the job, while not being truly spectacular for such a big car.
The new 7 Series is the first BMW Sedan with a double-wishbone front axle and the exclusive BMW integral V rear axle, made largely of aluminium.
Hydraulic rack-and-pinion steering with an on-demand steering assistance pump joins the world debut of optional Integral Active Steering, a combination of Active Steering on the front axle and speed-related rear-wheel steering.
Extending the performance envelope are new driver assistance features such as Dynamic Damping Control including Dynamic Driving Control, which are standard.
The Dynamic Driving Control button on the centre console varies the dampers, gearshift dynamics, as well as the throttle and steering assistance map. This offers the choice of Comfort, Normal, Sport and Sport Plus settings.
In Australia, customers are offered the following features, directly aligned with the 740i, as standard on the new 730d: Head-Up Display, High Beam Assistant, Adaptive bi-Xenon headlights with daytime running function, variable headlight beam distribution for better illumination around bends, including automatic turning lights, Automatic Variable Light technology (beam throw control with country / highway lights), Rear View Camera, and Cruise Control with Brake function.
The new BMW 730d will go on sale this month with a manufacturer’s list price from $198,800*.
*Manufacturer List Price excludes dealer charges, stamp duty, statutory charges and on-road charges, which are additional and vary between dealers and States/Territories. Customers are advised to contact a BMW dealer for all pricing inquiries.