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Safety, comfort, performance, price

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Options list, subtle styling update

IF you were starting to think that your 1999 S-class Mercedes-Benz was maybe getting a little long in the tooth, now is a time to rejoice.

To mark its fourth year on the Australian market, the company has updated the S-class in ways that at some level are very meaningful and at others, well, quite superficial.

The meaningful stuff essentially focuses on safety, although there are a few hedonistic gestures such as more comfortable seats, and a big boost in power for the entry level V6-engined versions.

The safety upgrades include a pre-emptive accident-detection system, called Pre-Safe, that sets the car's interior up in the moments before the accident actually happens to give driver and passengers optimal protection.

The Benz reads what is going on dynamically to adjust the front seats, tension the seatbelts and, if the car is skidding, also close the sunroof. The system takes its data from existing systems, including stability control and Brake Assist, and was in development for six years.

Importantly, Mercedes says all the actions taken to prepare for the impending accident do not restrict "the freedom of the driver or the driveability of the car" and, if the accident actually fails to eventuate, everything can be returned to its original position.

The latest S-class also gets updated accident severity detection that activates the seatbelt pretensioners earlier, while the front passenger's weight is now also taken into account as the car thinks about whether to trigger one or both of the airbag inflation stages.

This is on top of the existing Mercedes systems including a battery of airbags placed around the interior, plus sidebags at the rear, and a body constructed around the now-universal central "safety cage" principle.

The S-class is more comfortable, too. The front seats, always a good prospect for a long spell on the road, are now slightly softer and therefore slightly better at containing passengers during cornering forces, while still providing good support.

Equipment levels have been lifted, too, with all S-class models now getting a TV (with a larger screen, and on top of the already-standard GPS navigation system) as well as Park Distance Control.

Customers opting for a six-cylinder S-class benefit significantly, too. The capacity of the three-valves-per-cylinder V6 has been increased from 3.2 litres to 3.7 litres, which means a lift from 165kW to 180kW, and a decent gain in torque from 315Nm to 350Nm.

As well, the company is now making a six-cylinder long-wheelbase version available for the first time, which means it is possible to step into a Mercedes limo for (just) under $200,000.

The long-wheelbase cabin, as you would imagine, is cavernous, more than most people would ever really need. It delivers 120mm more legroom than a regular (short-wheelbase) S-class, which is not that bad in the first place.

The (adjustable) back seats are plush and supportive and there are twin, illuminated vanity mirrors that fold down from the roof on either side, as well as a rear-window shade and a control that allows the passenger side front seat to be manipulated from the rear.

The boot (but not the doors at S350 level) has a soft-close function as well as a lever that is normally tucked out of sight to avoid soiled fingers if the car is dirty.

Because the extra wheelbase length only add 30kg to the V6 S-class (for a total of 1840kg), the on-road performance isn't severely dented. This is not a highly stressed engine, and develops enough torque to deliver strong acceleration without needing to be pressed too hard.

It's not as smooth as a Benz V8, yet is still refined enough to create a suitably luxurious driving experience. It will accelerate to 100km/h in a not-unreasonable 7.6 seconds while returning relatively impressive fuel economy that will see the trip computer calculating an around-town figure of just under 13 litres per 100km.

With its cushy air suspension, the S-class makes the most of the long wheelbase to provide a ride that can only be described as sumptuous.

The adaptive damping system allows the driver to decide between a ride that is either indulgently plush or quite firm, and also incorporates a ride-height function that sits the car snug and low for high-speed freeway driving, or increases the ground clearance for rough roads.

The Mercedes also steers and handles like something smaller. Perhaps contradicting the soft ride and reasonably hefty body, it responds to the steering with precision and is quite happy to follow the tight line even when being pushed. The driver needs to try relatively hard to activate the stability control system.

The transmission is a smooth, adaptive five-speed sequential automatic, with the usual Benz sideways action for moving up and down through the ratios.

Cruising on the highway with the (optional) Distronic cruise control, the S350 is very easy to live with as speed moves up and down to match the traffic flow, even applying the brakes quite firmly if the vehicle in front slows suddenly.

Standard gear includes the Mercedes speed-limiter that keeps the car within a pre-set limit when driving around town. The operation lacks the simplicity of a regular, straight-forward Mercedes cruise control, although it still rates as one of the easiest and most intuitive systems to use.

It allows toggling upwards, km/h by km/h, by moving the lever towards the steering wheel, but can't be toggled downward by anything less than 10km/h increments - which can be a bit of a nuisance.

If you thought the S350 might feel like a slightly watered-down long-wheelbase S-class, then you're likely to be surprised, both by its on-road performance and the levels of interior luxury.

Yes, it's still a $190,000-plus car but, as we said earlier, it's been a while since a long-wheelbase S-class has been available for less than $200,000.

And if you are thought the latest iteration of the Mercedes grille (it's deeper and more vertical than before) might instantly date your almost-new 2002 S-class, don't worry about it.

The enlarged grille, and the refashioning of the below-bumper air intake is so subtle most people will have to directly compare old with new to detect the differences. But it is nice to see Mercedes erring on the side of boldness.