Oldsmobile Silhouette Back Up Light Bulb Size

Additional Notes

• The Oldsmobile Silhouette back up light specifications span model years 1990 through 2004, with four distinct bulb types used across that period: 2456, 3156, 2356, and 3057.
• The 3057 bulb is the most frequently specified type, covering the Oldsmobile Silhouette from 1990 through 1996. It is a dual-filament wedge bulb in the T25 form factor, rated at 12V with filaments drawing 27W and 7W respectively.
• The 2356 bulb is the second most commonly specified type, fitted to model years 1998-2001. It is a dual-filament bulb with a BAY15d bayonet base, operating at 12V.
• The BAY15d bayonet base of the 2356 uses an offset pin arrangement to prevent incorrect insertion, which is a key physical distinction from wedge-base bulbs such as the 3057 and 3156.
• The 2456 bulb is specified for 1997, 2002, and 2004. It is a festoon-style bulb rated at 12V and is classified as a specialty application type under the ANSI standard.
• The 3156 bulb is specified exclusively for the 2003 model year. Unlike the 3057 and 2356, it is a single-filament wedge bulb in the T25 form factor, rated at 12V and 27W.
• Although the 3057 and 3156 share the T25 wedge form factor, the 3057 carries a dual filament while the 3156 carries only a single filament, making them non-interchangeable despite their physical similarity.
• The 2003 model year Oldsmobile Silhouette is the only year in the specification set to use the single-filament 3156, setting it apart from all adjacent model years.
• All four bulb types in these specifications conform to ANSI standards applicable in both the United States and Canada, and all operate on a 12V electrical system.
• The 1997 model year uses the 2456 festoon bulb, while the immediately preceding year (1996) uses the 3057 wedge bulb and the immediately following year (1998) uses the 2356 bayonet bulb, indicating that no single bulb type carries across those three consecutive years.