The Jeep FC150 front and rear turn signal bulbs use 1034 or 1154 size bulbs depending on production specifications. The replacement chart covers 1957 to 1966 model years with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Jeep FC150 uses two distinct bulb types across its front and rear turn signal positions: the 1034 for the 1966 model year and the 1154 for the 1957 model year.
Both the 1034 and 1154 are ANSI-standardized bulbs recognized in the US and Canada, and both share the BAY15d bayonet base, a dual-contact base design that physically accommodates two filaments within a single housing.
Both bulbs are dual-filament types, meaning a single unit serves two lighting functions, typically combining a brighter filament for turn signaling with a dimmer filament for running or parking light duty.
The 1034 operates at 12V with a 21/5W output, where the higher wattage corresponds to the turn signal filament and the lower wattage to the secondary filament.
The 1154 is rated for either 6V or 12V operation, reflecting its origin as an older design intended for vehicles that may have used either voltage system.
Both the 1034 and 1154 are described as variants of the 1157, a widely used dual-filament bulb, though neither is a direct substitute for it despite the shared BAY15d base, as voltage and wattage differences affect compatibility.
The same bulb size applies to both the front and rear turn signal positions within each model year, meaning the 1966 FC150 uses the 1034 at all four turn signal positions and the 1957 uses the 1154 at all four positions.
The shift from the 1154 in 1957 to the 1034 in 1966 reflects a transition from a dual-voltage design to a fixed 12V specification, consistent with the broader automotive industry standardization on 12V electrical systems during that period.