The Pontiac G8 front turn signal requires a 2357NA bulb size while the rear turn signal uses a 1156NA bulb size. The replacement chart covers 2008 to 2009 vehicle production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Pontiac G8 uses two distinct bulb types across its front and rear turn signal positions for the 2008-2009 model years, with each position requiring a specific filament configuration.
The 2357NA is the front turn signal bulb for the Pontiac G8. It is a dual-filament bulb, meaning it carries two independent circuits within a single housing, allowing it to serve more than one lighting function simultaneously.
The 2357NA operates at 12 volts and draws 26.9 watts on its primary filament and 8 watts on its secondary filament. The difference in wattage between the two filaments reflects their separate functional roles.
The 2357NA uses a BAY15d bayonet base. This base type features two offset pins at different heights, a design that prevents incorrect insertion and ensures the correct filament is aligned with each circuit.
The rear turn signal position across both model years uses the 1156NA, a single-filament bulb rated at 12 volts and 21 watts. Its single-filament design means it serves one dedicated lighting function.
The 1156NA uses a BA15s bayonet base, which has a single pin and is not interchangeable with the BAY15d base of the 2357NA. Substituting one for the other is not physically compatible due to the differing base configurations.
Both the 2357NA and 1156NA feature natural amber glass, which produces the amber turn signal color directly from the bulb rather than relying on a colored lens to filter white light.
Both bulb types conform to ANSI standards applicable in the United States and Canada, indicating they meet a defined set of performance and dimensional criteria recognized across North American markets.