40831 is used to describe the area that was San Jose and Salinas in the 80's and before. The original area code for Salinas was 408, shared by San Jose, Santa Cruz and encompassed areas. Salinas got its own area code in the early to mid nineties. 831. The term is used by those in Salinas who are old enough to remember when Salinas was in the 408.
Where you from? I'm From the 40831, yadadda?