The Pontiac Aztek front turn signal requires either a 3157NA or 3057 bulb size, while the rear turn signal uses a 3157 bulb size. The replacement chart covers 2001 through 2005 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 Aztek uses three bulb types across its front and rear turn signal positions: the 3157NA, 3057, and 3157. All three conform to ANSI standards applicable in the United States and Canada.
All three bulb types share the same T25 wedge base, dual-filament construction, and 12V/27W/7W electrical ratings, making them electrically and physically similar in most respects.
The dual-filament design in these bulbs supports two brightness levels within a single housing, which allows one bulb to serve both a running light function and a higher-intensity turn signal function simultaneously.
The 3157NA used in the Pontiac Aztek front turn signal positions for 2004-2005 features natural amber glass. This coloring shifts the emitted light to amber at the bulb itself rather than relying on a colored lens to produce the required signal color.
The 3057 was fitted to the front turn signal positions of the Aztek for 2001-2003. It shares the same T25 base and 12V/27W/7W ratings as the 3157NA and 3157 but lacks the amber glass coating of the 3157NA.
The 3157 was used in the rear turn signal position across all Aztek model years from 2001-2005, representing the only bulb type that remained unchanged throughout the entire production run covered by these specifications.
Although the 3057 and 3157 share identical voltage and wattage ratings, they are not confirmed interchangeable by these specifications. The front and rear positions are listed with distinct part numbers, and substitution between them is not indicated.
The front turn signal bulb type changed between the 2003 and 2004 model years, shifting from the 3057 to the 3157NA. This represents a mid-production specification change specific to the front position on the Pontiac Aztek.