Yeah well it ain't just Datsuns.

I had a '84 Toyota 4 Runner.

The ignition key would also work on my '89 Toyota ute.

In a carpark one day, saw a lady trying to get into her Toyt,

having locked the keys inside.

Yep, you guessed it. the 4 Runner's key not only opened the door, it also worked on her cars ignition.

Rick.

Since there are only so many combinations of key patterns the rumor is the manufactures send the cars with matching keys to east and west coast.Once when I was in a training school we had a pool of the same type cars.One night we got in one and went out for a night of bar hopping.When we got back to the hotel we found we had taken a car that the key fit and was a pool car but the wrong one.The guy that the car was signed out to had reported it stolen!!!Glad we made it back to the hotel!!I also had that happen at a hotel once.Me and a friend in a drunken easter weekend went to the right location,wrong floor.The key opened the door and we caught a couple enjoying their weekend.After that I always deadbolt my hotel door!A friend in the army told me ANY gm key will crank a military hummer.Guess that would be a mess to try and find the correct hummer when they all look alike huh?