Mercedes C 180 d review

Mercedes C 180 d is an attractive offer for fleets in Europe. We drove it to see how much Mercedes is in this saloon powered by a Renault origin diesel engine.

Daimler and Renault-Nissan has succeeded to establish a very  productive partnership. 12 projects are going on across three continents.

Mercedes supplies the A/GLA platform for the new Infiniti Q30/QX30, the 2.2 liter diesel and 2 liter petrol for Infiniti brand, while Renault supplies Twingo platform and 3 cylinder naturally aspirated and turbo for smart fortwo/forfour and  delivers 1.5 litre diesel engine for Mercedes compact range and 1.6 liter diesel for Mercedes C-Class.

Why a 1.6 diesel engine with Renault origin in a luxury saloon like Mercedes C-Class? It would fit a such engine the expectations of Mercedes customers?

It could be surprinsing but the 1.6 liter diesel engine is offered only in the C-Class and not in the A/B/CLA/GLA compact range. Why not? Because there are no fleet demands for cars like GLA, while C-Class saloon is an important pylon for Mercedes offer in the fleet segment.

With 99 g/km CO2 emissions, the 1.6 liter diesel in both versions with 116 HP and 136 HP is very attractive for taxes in Europe, being the most efficient diesel in the premium segment. Price is another advantage along with low taxes.

C 180 d with 116 HP and 280 Nm is priced at 34,063.75 euro and the C 200 d with the same 1.6 liter diesel (136 HP and 300 Nm) costs 36,443.75 euro, while the C 220 d with the traditional Mercedes 2.2 liter diesel engine 170 HP reaches 38,823.75 euro.

The price difference is important at the first glance but we speak also about different standard levels of equipment. Like the C 160 and C 180 (both with 1.6 liter petrol 129 and 156 HP), the C 180 d has 16 inch steel alloy wheels and monozone clima. C 220 d and C 200 comes with 16 inch light alloy wheels and dual zone clima as standard. On the other hand, C 180 d could be ordered with all technical innovations from the new C-Class including the new Airmatic suspension (only in combination with Exclusive or Avantgarde line like for all other versions).

Made by Renault, modified by Mercedes

The Renault  origin 1.6 liter diesel has been modified by Mercedes. The OM 626 code name engine is the first passenger diesel in the world to use steel pistons. Thanks to reduced friction and better thermal behaviour they offer clear advantages in terms of fuel consumption over aluminium pistons. The crankcase of the new diesel engine, which is characterised by particularly comfortable NVH properties, is made of cast iron, the cylinder head of an aluminium alloy.

With 4 valves per cylinder and a variable turbine geometry the common-rail direct injection system of the new small diesel engine operates at a maximum injection pressure of 1600 bar. It is produced by Renault and assembled in part in Mercedes factory from Bremen. Technology modules specific to Mercedes-Benz make the engine more efficient. They include the ECO start/stop function, the ancillaries and a special dual-mass flywheel that better compensates imbalances and makes a balancer shaft unnecessary. The engine control unit with additional functions ensures a driveability that can be rightfully expected from a Mercedes.

Very silent but less dynamic

The Renault 1.6 liter diesel is known for very low noise even when you reach close to the red zone. And you never feel its diesel origin when you push hard. The engine makes no exception in Mercedes from this point of view.

The engine compartment is very well soundproofing and the first subjective impression is that the 1.6 liter diesel is even more silent than the 2.2 liter Mercedes engine.

The engine is very flexible and the power flow is progressive up to close to the red zone at 4,600 rpm.

But the pulling power is rather disappointing. The overtaking maneuvers takes too long time and the accelerations from 0 to 100 km/h are much slower than in case of 2.2 liter diesel.

You need 11.1 (11.6) seconds to reach 100 km/h in C 180 d compared with 7.7 (7.4 with 7 G-Tronic automatic gearbox) in C 220 d. The gap was expected due to the big differences in torque: 280 Nm between 1,500-2,800 revs compared with 400 Nm between 1,400-2,800 revs. A much better results offers C 200 d with 136 HP. It goes to 100 km/h in 9.7 (10.2 seconds) but is costs 2,400 euro more than the C 180 d.

But as soon as you reach an established cruise speed, the C 180 d runs smoothly and very pleasant. The 1.6 liter diesel engine fulfills the Mercedes standards from the refinement point of view. It reaches a 204 km/h top speed compared with 234 km/h top speed for C 220 d.

In the end only price difference is the main advantage because there are no benefits in therms of fuel consumption. The official consumption figures for C 180 d and C 220 d are very very close: 4.7/3.5/3.9 l/100 km for C 180 d compared with 4.8/3.4/4.0 l/100 km for C 220 d.

The fuel consumption in real life are – unexpected – also extremely close. In both cases values of 5.3-5.5 l/100 km could be reached in normal driving situations.

We can look to this result in two ways: the Mercedes 2.2 liter diesel engine is already a very economical engine but we expect also a much lower consumption for a such downsizing operation from 2.2 to 1.6 liter.

Verdict|The new C 180 d is offered at a very low price for a Mercedes diesel saloon which makes it very attractive for fleets due to low price and very low emissions. It fulfills the Mercedes standards in therms of noise levels and refinement but is much more lazy than the 2.2 liter diesel and the downsize operation had no effect regarding fuel consumption.