There is a database (I am sorry I can't remember off the top of my head) that has all the bulletins a repairs "recalls" for the various makes and models of cars. The car company is only required to tell you if NHTSA tells them to (for safety). All other recalls are at the discretion of the car company (they may decide to do official recalls and such for various reasons).
A prime example - my wife's volt had leaking battery coolant (battery coolant radiator had a hole) - service high voltage charging system warning (from low coolant), the car won't charge because the battery coolant is too low/leaking - again apparently this isn't a safety issue even though it defeats the purpose of the car. There is a bulletin for the repairs - GM has identified the problem, put out an internal bulletin that all volts get a free battery coolant check (air check for leaks) and repairs done if under the 60k warranty for free. This was never passed out to consumers, and the bulletin even listed that it would not be given to consumers, but dealerships should do the check (and repairs) on the vehicles next maintenance when brought in or when a customer brings in the car with this error.
Sadly, not all dealerships are nice. We took it to one dealership whom not only charged us for the coolant check (air pressure) but wanted us to pay the $1500 to repair the battery coolant radiator. Luckily we got a bad vibe from them and decided to take it to a different dealership and on the way to the second one, I was poking around and found the recall/bulletin site and found this exact bulletin. The other dealership was trying to scam us. Luckily my wife's volt adviser was able to get our money back from the previous dealership (they still charged us to do the coolant air pressure test on the car - which should have been free). Second dealership did everything for free under warranty. Awesome!