Under the hood: There's more to the Mercedes C-Class than just good looks

More economical, better equipped and with massive interior upgrades, the Mercedes C-Class just got better than it needs to be right now.

But when it goes on sale in SA at the beginning of August, will 6,500 new parts be enough to keep the Benz mainstay ahead of the next contenders from Audi and BMW?

Benz fully expected either the BMW 3 Series or the Audi A4 to have clambered up to equal footing with the C-Class by now, but they haven’t, and neither have the ensemble players such as Jaguar, Alfa Romeo or Lexus.

Yet a new 3 Series is in the works and an A4 facelift is around the corner, both of which will hit the C-Class like a wave in the next year, so this facelifted version has about three years to fight on.

It’s also one of those mid-cycle facelifts that aren’t obviously a facelift. Benz insists it has changed almost 6,500 parts in the cycle shift, so the changes run far deeper than the skin.

Visually, the upgrades are different for each specification and the car can look like a conservative fuddy duddy or a classy baby S-Class, depending on which boxes you tick and how much extra cash you pay.

There are new bumpers and every powertrain variant now has its own exhaust treatment, though the biggest change in the face are made by choosing the sportier "winged" grille or the conservative traditional one.

The next biggest agent of change are the headlights, which start with old-school halogens for fleets in the wagon, move to the LEDs that are standard in the rest of the range and top out with the 84 rotating LEDs in the Multibeam LED lights, promising 650m of vision at night.

About 80% of the C-Class’s electronics architecture is new, or, at least, it’s new to the C-Class. Mostly it’s adopted from the S-Class, which means S-Class infotainment functions, S-Class driver assistance systems and S-Class navigation.

For the driving, that means the active cruise control edges closer to autonomy by slowing down when the navigation system senses tighter bends or intersections (which is an option), while its sensors for detecting other road users has taken a leap forward. Between its radar and camera sensors, Benz insists it can draw its own 3D picture of the first 90m in front of the car, plus a 2D picture for up to 1km.

The cabin was a leap forward for Benz when the current C-Class debuted, though time was catching up with it. It’s good to see, then, that the new model has taken another leap, with fit and finish unseen in any BMW of this class and even approaching Audi.

The biggest thing you notice, though, is that it doesn’t score the E and S-Class double digital screens, or the twin screens of the junior, cheaper A-Class, for that matter.

Retooling the entire dash would have been too expensive, so there’s an optional fully digital instrument cluster and the infotainment screen has been boosted to 10.25 inches, though it’s not a touchscreen unit.

There are new paintcodes and new colours inside, too, plus new trim materials such as oak and walnut, and the core layout of the C-Class interior remains.

The entry-level C200’s adoption of the nine-speed automatic transmission means the end of manual gearboxes in yet another nameplate, with across-the-board self-shifting now a C-Class hallmark.

All the four-cylinder engines are new, starting with the M254, which has shrunk to just 1.5l of four-cylinder petrol engine. It joins the fleet in the entry-level C200, with its twin-scroll turbocharger helping it to 135kW of power and 280Nm of torque.

It introduces mild-hybrid, 48V electrical power to the C-Class, plus a particulate filter (of a kind that was diesel-only fare half a generation ago). The mild-hybrid part of the engine is an electric starter-generator module that runs its own 48V power system for faster recharging and discharging, though the rest of the car runs on conventional 12V power.

If the car is braking, the generator can push up to 12kW of power back into the 48V battery, and it can throw up to 10kW and 160Nm of that back into the crankshaft, which helps the engine’s revs rise with far less effort than just burning petrol.

It gives the C200 sedan a claimed economy figure of 6.5l/100km and it emits 136g/km of CO2, which aren’t bad numbers if they can be replicated in the real world.

It has a new trick called trumpet honing, where the engine’s cylinder walls are no longer straight, but slightly widen towards the bottom to reduce friction from the piston skirts. The hollow valve stems are filled with sodium to keep the air-fuel mixture as cool as possible and it uses Camtronic, a two-stage valve-lift system — you know, like Honda has been using for more than 20 years.

It’s a good, clean engine to drive, with a lot more low-down performance than you’d normally credit from such a small powerplant. The trouble with it is that while it’s smooth, it’s not especially pleasant to listen to when it’s being worked hard. And it’s only a 1.5, so working hard is sometimes unavoidable.

The tone at the coalface is a bit too thrashy and the effort a bit too obvious for a car carrying a three-pointed star, though that only comes across in the vocals, not the vibrations.

The electric boosting has been seamlessly integrated into the powertrain, to the point at which it’s impossible to know where the electric boosting stops and the four-pot takes over completely.

Its Eco mode is the car’s truly happy place, with the engine capable of switching off completely at highway speeds to "sail" to save fuel. The only downside here is that it’s not sufficiently developed to allow the electric motor to throw in a bit of torque here and there to keep the petrol motor switched off on small rises.

Down low, the thing jumps off the line with a surprising alacrity as 160Nm of instant electric power fill in until the turbo can talk the petrol engine’s torque curve into waking up. It’s a languid thing for wafting along and moving easily from one place to another, though it’s caught short anytime you want it to lift its skirts. That’s when you find the steering to be Audi-like in its numbness, the engine exertions sound all too obvious and the chassis’ balance undone by the suspension setup’s disinterest in piling on pace.

There’s a 2.0l turbo four in the C300, but we never had seat time in it and, besides, it doesn’t get the C200’s more interesting mild-hybrid boost. It does get another 13kW of power, though, taking it up to 190kW and 370Nm of torque.

There’s been a heap of things transpiring over at Benz’s diesel department, and I’m not just talking about the legal advisers telling everyone to shut up about thermal switching (which turned off most emissions controls below 6°C or above 26°C).

Now, the OM654 2.0l diesel is fine down to -7°C and up to 35°C, so Benz insists. The four pot has multiple exhaust gas recirculation, plus it has snuggled the SCR particulate filter and the SCR catalytic converter right up close to the turbocharger to shorten the cold- running phase.

For low-down strength and sheer economy, the C-Class range doesn’t get any better than the diesel engines and the pick of them is in the C220d. This is the engine with 143kW of power and 400Nm of torque from only 1,600r/min, and it thumps out emissions figures of 117g/km of CO2 in sedan form, for a claimed average figure of 4.4l/100km.

It has taken a huge step towards reducing the noise, vibration and harshness levels that dogged its otherwise-impressive predecessor. It’s a much more refined motor than it was before, though it still hasn’t toppled BMW’s equivalent diesel fours as still the pick of the premium bunch.

It’s very strong at low engine speeds and it’s flexible everywhere. It feels as though this is the engine-transmission package the C-Class was really born to carry, and it wears it well.

Again, its handling package feels stolid and conservatively safe and comfortable rather than athletic. Keep it within that day-to-day handling envelope and you’ll struggle to find a complaint against it. Push it harder and it will do what you ask of it.

In terms of luxury and functionality, the C-Class remains a middle step between a 3 Series and an A4.

This article was originally published by The Business Day.
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