The Dodge Omni front side marker bulb size measures 168 or 1157, while the rear side marker bulb size measures 168. The replacement chart covers 1978 to 1990 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 Dodge Omni front side marker uses the 168 bulb for model years 1980-1990, while the 1978-1979 model years use the 1157 bulb instead.
The rear side marker on the Dodge Omni uses the 168 bulb across all listed model years, from 1978 through 1990.
The 168 is a T10 miniature wedge bulb rated at 12V and 4.9W, conforming to ANSI standards recognized in both the United States and Canada.
The 1157 is a dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21W high filament and a 5W low filament, also conforming to ANSI standards for the US and Canadian markets.
The BAY15d bayonet base of the 1157 bulb is a two-pin offset base, which physically prevents it from being inserted in the same socket orientation as a single-filament bayonet bulb, making it non-interchangeable with single-filament bayonet types.
The wedge base of the 168 bulb relies on wire leads bent outward to hold it in place within its socket, a design that differs fundamentally from the bayonet base of the 1157, meaning the two bulb types are not interchangeable.
The 1157 carries a significantly higher wattage than the 168, with its main filament drawing 21W compared to the 168's 4.9W, reflecting the different functional roles these bulbs serve across the model years in which they appear.
The front side marker socket on the Dodge Omni changed between the 1979 and 1980 model years, as the specification shifts from the dual-filament 1157 with a bayonet base to the single-filament 168 with a wedge base.