Mercury Marauder front turn signal bulbs utilize 3157NA, 1157, or 1034NA sizes, while rear turn signal bulbs use 3157 or 1157 sizes depending on model year. The replacement chart covers 1963 through 2004 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 1157 bulb is the most frequently specified type across the Mercury Marauder turn signal positions, appearing in the rear turn signal for every model year listed from 1963-1970 and in the front turn signal for the 1963 and 1970 model years. It is a dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21W high filament and 5W low filament.
The 3157 and 3157NA are dual-filament wedge bulbs in the T25 form factor, rated at 12V with a 27W high filament and 7W low filament. These types are specified for both the front and rear turn signals on the 2003-2004 Mercury Marauder.
The front and rear turn signal positions on the 2003-2004 Marauder use different bulb types despite sharing the same T25 form factor. The front position requires the 3157NA, which has natural amber glass, while the rear position uses the clear 3157. These two types are not interchangeable without affecting the color output of the lens assembly.
The 1034NA is specified for the front turn signal on the Mercury Marauder across the 1964-1969 model years, with the exception of 1966. It is a variant of the 1157 sharing the same BAY15d bayonet base and 12V, 21W/5W ratings, but it incorporates natural amber glass rather than a clear envelope.
The 1157NA is specified for the front turn signal on the 1966 Marauder. It shares the same BAY15d bayonet base and 12V, 21W/5W electrical ratings as both the 1157 and 1034NA, but like the 1034NA, it features natural amber glass. The 1157NA and 1034NA differ in designation despite similar characteristics, and substitution between them warrants verification against the original socket and housing.
All three BAY15d-based bulb types listed, the 1157, 1034NA, and 1157NA, share the same base configuration and wattage ratings. However, the presence or absence of natural amber glass distinguishes them, and using a clear bulb in a position specified for an amber-glass type may alter the apparent color of the signal if the lens itself is not amber-tinted.
The dual-filament design present in all listed bulb types serves two distinct functions within a single housing. The higher-wattage filament activates for the turn signal or brake signal, while the lower-wattage filament typically serves as a running or parking light, allowing one bulb to handle multiple lighting roles simultaneously.
The BAY15d bayonet base used by the 1157, 1034NA, and 1157NA features two offset pins that prevent incorrect insertion. This base type is a widely adopted standard in automotive lighting and is distinct from the wedge-style base used by the T25 3157 and 3157NA bulbs, meaning the two base families are physically incompatible with each other's sockets.
The front turn signal specification for the 1963 Marauder calls for the 1157, which is a clear-envelope bulb, while the 1966 front position uses the 1157NA with natural amber glass. Both share identical electrical ratings, but the glass color difference indicates that the lens or housing design likely differs between those model years.
The wattage step between the older BAY15d-based bulbs and the T25 wedge bulbs used in the 2003-2004 model years is notable. The 1157-family bulbs are rated at 21W/5W, while the 3157-family bulbs are rated at 27W/7W, reflecting a higher output specification in the later vehicle generation.