The Lincoln Aviator front inner turn signal uses a 3157NA bulb size, while front turn signals require a 906 bulb and rear turn signals use a 3057 bulb size. The replacement chart covers 2003 through 2005 model 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 Lincoln Aviator uses three distinct turn signal bulb types across its 2003-2005 model years: the 3157NA for the front inner turn signal, the 906 for the front turn signal in the mirror housing, and the 3057 for the rear turn signal.
The 3157NA and 3057 are both dual-filament T25 wedge bulbs rated at 12V with a 27W/7W power split, meaning the higher wattage filament serves the primary signal function while the lower wattage filament serves a secondary function such as running light duty.
The key distinction between the 3157NA and the 3057 is the glass envelope. The 3157NA features natural amber-tinted glass, which produces an amber signal output without relying on an amber lens, while the 3057 uses clear glass.
Because the 3157NA and 3057 share the same T25 wedge base and identical voltage and wattage ratings, they are physically interchangeable in terms of socket fitment, though substituting one for the other would affect the color output of the signal.
The 906 is a single-filament T10 miniature wedge bulb rated at 12V and 8W, a significantly smaller and lower-powered bulb than the T25 types used elsewhere on the vehicle, reflecting the compact space constraints of a mirror-mounted turn signal housing.
All three bulb types conform to ANSI standards applicable in both the United States and Canada, indicating standardized electrical and photometric performance requirements across North American markets.
The front turn signal position on the Lincoln Aviator (2003-2005) is located within the mirror assembly, which is a design arrangement that places the turn signal indicator on the side mirror rather than in the front fascia or headlamp cluster.
The 906 bulb used in the mirror-mounted front turn signal is not interchangeable with the T25-based bulbs used in the front inner or rear turn signal positions, as the T10 and T25 wedge bases differ in physical size and socket compatibility.