Which three Formula 1 Grand Prix wins have been won by two people sharing a car?

Three Grands Prix, the 1951 French, the 1956 Argentine and the 1957 British Grand Prix, were won by two drivers sharing a car.

https://en.m.wikipedia.org/wiki/List_of_Formula_One_Grand_Prix_winners

The above answer is correct. However, it raised questions about the circumstances where two drivers would share a car. Using Wikipedia, there is something of a theme with these three Grands Prix.

The 1951 French Grand Prix at Riems-Gueux (July 1) was won by Juan Manuel Fangio and Luigi Fagioli driving an Alfa Romeo. Fagioli was aged 53 years, 22 days and he still holds the record for the oldest driver to win a Grand Prix. The almost 374 mile (602 km) race distance is also a record. Mechanical problems saw Fangio take over his team mate's car at a fuel stop. Both were credited with the win with Fangio also setting the fastest lap of the race.

The 1956 Argentine Grand Prix (January 22) at Buenos Aires saw Ferrari car #34 driven by Luigi Musso (30 laps) and Juan Manuel Fangio (68 laps) shared the win. Fangio took over Musso's car after earlier mechanical problems.

The 1957 British Grand Prix (July 20) was raced at Aintree, near Liverpool. Driving Vanwall car #20, the race was won by two British drivers, Tony Brooks (26 laps) and Stirling Moss (64 laps). Earlier, Moss had won the pole position in Vanwall car #18, so the assumption is that mechanical problems saw him take over Brooks' vehicle.