Citroen C6

Citroen C6: Which Version Should You Buy?

The Citroen C6 was offered in a single generation from July 2005 through December 2012, so choosing one is mainly a question of engine and transmission rather than generation. All five listed versions are Sedan models with FWD, a 72-litre fuel tank, independent hydropneumatic suspension at both ends, and front ventilated disc brakes.

The Citroen C6 was offered in a single generation from July 2005 through December 2012, so choosing one is mainly a question of engine and transmission rather than generation. All five listed versions are Sedan models with FWD, a 72-litre fuel tank, independent hydropneumatic suspension at both ends, and front ventilated disc brakes. The key trade-off is clear: the 3.0 AT diesel delivers the strongest performance, the 2.2 MT records the lowest combined fuel consumption, and the 3.0 AT gasoline version has the highest fuel use.

Citroen C6 generation and version choice

The 1 generation covers 2005–2012 and contains five versions: 2.2 MT, 2.2 AT, two versions named 3.0 AT, and 2.7 AT. The identical 3.0 AT names refer to different engines: one is a 240 hp Diesel with 2,993 cc, while the other is a 211 hp Gasoline engine with 2,946 cc. There is no second generation or separate restyling listed in the supplied data, so no generation-to-generation changes can be compared.

Because every version belongs to the same Sedan generation, the suspension layout does not decide the choice: each has Independent hydropneumatic front and rear suspension. Gearbox preference narrows the field more effectively. The 2.2 MT is the only Manual option, while the other four versions use an Automatic gearbox. Every gearbox has 6 speeds, and every version is FWD.

Citroen C6 engine specs and horsepower

The 3.0 AT diesel has the highest specific output at approximately 80.2 hp per litre. The 2.2 MT and 2.2 AT diesels each produce approximately 78.0 hp per litre, the 2.7 AT diesel produces approximately 75.0 hp per litre, and the 3.0 AT gasoline version produces approximately 71.6 hp per litre.

Torque separates the two engines carrying the 3.0 AT name particularly strongly. The 240 hp Diesel produces 450 Nm, which is 160 Nm more than the 290 Nm Gasoline version. Its peak torque also arrives at 1,600 rpm rather than 3,750 rpm. The 2.7 AT is close to the stronger 3.0 AT diesel on torque, trailing it by only 10 Nm, but it has 36 hp less power.

Citroen C6 performance and mpg comparison

For minimum recorded consumption, the 2.2 MT is the strongest choice. Its combined figure is 6.6 L/100 km, only 0.2 L/100 km below the 2.2 AT, but its city figure is 1.5 L/100 km lower. It is also 1.0 second quicker from 0 to 100 km/h and has a top speed 3 km/h higher than the otherwise mechanically similar 2.2 AT.

The 3.0 AT diesel is the performance choice. It reaches 100 km/h in 8.5 seconds and 240 km/h, making it 0.8 second quicker and 10 km/h faster than the 2.7 AT. Despite that advantage, its combined consumption is 1.3 L/100 km lower than the 2.7 AT figure. Its highway result of 5.2 L/100 km is also the lowest recorded for any listed version.

The 3.0 AT gasoline version reaches 100 km/h in 9.4 seconds and has a 230 km/h top speed. Against the 2.7 AT, it is 0.1 second slower while matching its top speed, and it uses an additional 2.5 L/100 km on the combined cycle. Against the 240 hp 3.0 AT diesel, the gasoline version has 29 hp less, takes 0.9 second longer to reach 100 km/h, and consumes 3.8 L/100 km more on the combined cycle.

Consumption figures are supplied in L/100 km rather than mpg. An mpg value is therefore not measured in the data.

Citroen C6 dimensions, weight, clearance and wheel specs

Overall length, width, height and other exterior dimensions are not measured. Wheel sizes are also not measured for any version. Ground clearance is 150 mm for the 3.0 AT diesel and 3.0 AT gasoline versions; it is not measured for 2.2 MT, 2.2 AT or 2.7 AT. Fuel-tank capacity is 72 litres throughout the range.

The 3.0 AT gasoline version is the lightest at 1,820 kg, while the 3.0 AT diesel is the heaviest at 1,873 kg, a difference of 53 kg. Power-to-weight calculations reverse that simple weight ranking: the 3.0 AT diesel carries approximately 7.8 kg per horsepower, the 2.7 AT approximately 9.2 kg per horsepower, the 3.0 AT gasoline version approximately 8.6 kg per horsepower, and both 2.2 versions approximately 10.7 kg per horsepower.

Citroen C6 suspension, brakes and emissions

All five versions use Independent hydropneumatic suspension at the front and rear, so there is no version-level difference in the listed suspension design. Front brakes are Ventilated disc throughout. Rear brakes are ventilated discs on 2.2 MT and both 3.0 AT versions, while 2.2 AT and 2.7 AT have rear discs without ventilation in the supplied specification.

The 2.2 MT and 2.2 AT are Euro 4, with CO₂ output not measured. The 3.0 AT diesel, 2.7 AT and 3.0 AT gasoline versions are Euro 5. CO₂ output is 195 g/km for both 3.0 AT versions and 230 g/km for the 2.7 AT.

Reliability, engine-oil requirements, engine-mount condition, engine-swap suitability and mechanical problems are not measured in the data. They therefore cannot be used to rank these versions.

Which Citroen C6 version should you buy?

Choose 2.2 MT if recorded economy and a Manual gearbox matter most. Its 6.6 L/100 km combined consumption is the lowest, and it outperforms the 2.2 AT in acceleration, top speed and every listed consumption category while having the same 170 hp, 370 Nm and 1,825 kg kerb weight.

Choose 2.2 AT if an Automatic gearbox is essential and the lowest-displacement engine is preferred. Compared with 2.2 MT, the automatic costs 1.0 second in the 0–100 km/h run and increases combined consumption by 0.2 L/100 km, without changing power, torque, displacement or kerb weight.

Choose 3.0 AT with 240 hp if outright capability is the priority. It has the highest power, highest torque, fastest acceleration and highest top speed. It also combines those results with 7.4 L/100 km consumption, only 0.8 L/100 km above the economy-leading 2.2 MT and 1.3 L/100 km below the 2.7 AT.

Choose 2.7 AT if 204 hp, 440 Nm and Automatic transmission match the desired specification, but its numbers do not produce a clear performance-or-economy advantage over the 240 hp 3.0 AT diesel. The 3.0 AT diesel adds 36 hp and 10 Nm, accelerates 0.8 second faster, reaches 10 km/h more, and consumes 1.3 L/100 km less on the combined cycle.

Choose 3.0 AT with 211 hp if the required engine is specifically the Gasoline, naturally aspirated V-shaped 6-cylinder option. It is the only Gasoline version and the only version with no boost. Numerically, however, it records the highest city, highway and combined fuel consumption and cannot match the 240 hp 3.0 AT diesel for power, torque or acceleration.

No price or sale data is supplied, including information for the USA. Consequently, purchase price, availability and value for money cannot be measured here. On specifications alone, the 2.2 MT is the economy-led selection, while the 240 hp 3.0 AT diesel is the strongest all-round performance choice.