Chevrolet SS front turn signal bulbs use 7443NA or 7444NA sizes, while rear turn signal bulbs use 7440NA size. The replacement chart covers 2014 through 2017 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Chevrolet SS uses T20 wedge-base bulbs across all front and rear turn signal positions for the 2014-2017 model years.
The 7440NA is a single-filament T20 wedge bulb rated at 12V and 21W, and it serves as the rear turn signal bulb on the Chevrolet SS for all four model years in the specifications.
The front turn signal on the 2015-2017 SS uses the 7443NA, a dual-filament T20 wedge bulb rated at 12V with a 21W high filament and a 5W low filament.
The 2014 SS front turn signal takes the 7444NA rather than the 7443NA used in later model years. Both are dual-filament T20 wedge bulbs with identical 12V, 21W/5W ratings.
Because the 7443NA and 7444NA share the same T20 wedge base and electrical ratings, the practical difference between them is a manufacturer designation rather than a functional one, though fitment should follow the year-specific specification.
All three bulb types in these specifications carry the "NA" suffix, which denotes natural amber glass. This coloring produces an amber signal output without relying on a colored lens or housing to achieve the required turn signal hue.
The dual-filament design of the 7443NA and 7444NA allows a single bulb to serve two functions, with the 5W filament typically operating as a parking or daytime running light and the 21W filament activating as the turn signal.
All bulbs in these specifications conform to ANSI standards applicable in the United States and Canada, indicating compliance with North American automotive lighting regulations.