Petrol Engines | Year | Maximum power - Output - Horsepower (hp) | Engine size - Displacement - Engine capacity | Compare to another car |
| C6 3.0i Specs | 2006 | 211 | 2946 cm3 (179.8 cu-in) |  |
Diesel Engines | Year | Maximum power - Output - Horsepower (hp) | Engine size - Displacement - Engine capacity | Compare to another car |
| C6 170 HDi FAP CAS Business Specs | 170 | 2179 cm3 (133 cu-in) | | |
| C6 170 HDi FAP CAS Exclusive Specs | 170 | 2179 cm3 (133 cu-in) | | |
| C6 2.2 HDi Specs | 2006 | 173 | 2179 cm3 (133 cu-in) | |
| C6 2.7 HDi Specs | 2006 | 204 | 2721 cm3 (166 cu-in) | |
| C6 HDi 170 FAP CAS Business Specs | 2010 | 170 | 2179 cm3 (133 cu-in) | |
| C6 HDi 170 FAP CAS Exclusive Specs | 2010 | 170 | 2179 cm3 (133 cu-in) | |
| C6 V6 HDi 240 CAS Exclusive Specs | 241 | 2993 cm3 (182.6 cu-in) | | |
| C6 V6 HDi 240 CAS Exclusive Specs | 2010 | 241 | 2993 cm3 (182.6 cu-in) | |
