The year that a vehicle becomes exempt from smog inspections in California depends on its model year and type. Here are the different exemptions:

• Gasoline-powered vehicles that are less than 4 model years old are exempt from smog inspections for the first 8 years that they are registered.
• Gasoline-powered vehicles that are 1975 model year or older are exempt from smog inspections.
• Gasoline-powered vehicles that are 1983 model year or older are exempt from smog inspections if the proposed California Assembly Bill 210 is passed.
• Diesel-powered vehicles that are 1997 model year or older with a gross vehicle weight rating of 14,001 pounds or greater are exempt from smog inspections.
• Other exemptions include collector cars that are 25 years or older and classic or antique cars.

Its important to note that these exemptions may change due to new laws or regulations.