| Marques | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
| Marques | # | Date | Liens | Photos | Forums | Histoire |
| O.M. (Italy) | 1918 - 1934 | --> 2 |
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| Oakland (United States of America) | 1 | 1907 - 1931 | --> 4 |
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| Ohta (Japan) | 5 | 1934 - 1957 | --> 6 |
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| Oldsmobile (United States of America) | 403 | 1896 - 2003 | --> 22 | --> 189 |
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| Omega-Six (France) | 1 | 1922 - 1930 | --> 3 |
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| Opel (Germany) | 661 | 1898 - | --> 32 | --> 375 | 865 msg |
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| Orca (Switzerland) | 1 | 2003 - | --> 4 | |||
| Orient Express (Germany) | 1 | 1895 - 1903 | --> 4 |
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| Osca (Italy) | 5 | 1947 - 1967 | --> 11 |
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| Otto (France) | 1 | 1901 - 1914 | --> 3 |
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