Plymouth Trailduster front turn signal bulbs measure 1157, 1034NA, or 1157NA in size, while rear turn signal bulbs measure 1157 or 198 in size. The replacement chart covers vehicle production years spanning 1974 to 1981.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Plymouth Trailduster uses three distinct bulb types across its front and rear turn signal positions: the 1157, 1034NA, 1157NA, and 198.
The 1157 is the most frequently specified bulb in these listings, covering the front and rear turn signals for the 1979-1981 Plymouth Trailduster. It is a dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, mounted on a BAY15d bayonet base.
The BAY15d bayonet base found on the 1157 features offset pins, which physically prevent incorrect single-filament bulbs from being inserted into dual-filament sockets.
The 1034NA shares the same BAY15d bayonet base and 12V, 21W/5W electrical ratings as the 1157 but is distinguished by natural amber glass rather than a clear envelope. It is specified for the front turn signal on the 1977-1978 Trailduster.
The 1157NA is similarly a dual-filament BAY15d bulb at 12V, 21W/5W with natural amber glass, and it appears exclusively on the 1976 front turn signal position.
Because the 1034NA and 1157NA share the same base type and electrical ratings as the 1157, the primary functional difference is the amber tinting of the glass envelope, which produces a colored output without relying on a colored lens.
The 198 is a miniature wedge bulb of the T5 form factor, rated at 12V and 2W. It is a single-filament, low-wattage bulb and is not electrically or physically interchangeable with the dual-filament BAY15d bulbs used elsewhere in these specifications.
The 198 bulb is specified for the rear turn signal on the 1974-1978 Trailduster and for the front turn signal on the 1974-1975 models, making it the sole turn signal bulb type used across both positions during those earlier years.
The front turn signal position on the Plymouth Trailduster reflects a change across the production run, transitioning from the low-wattage 198 wedge bulb in 1974-1975 through the amber-glass BAY15d variants in 1976-1978 and settling on the clear 1157 from 1979 onward.
The rear turn signal position used the 198 bulb from 1974-1978 before switching to the 1157 for 1979-1981, meaning the front and rear positions shared the same bulb type only during the 1974-1975 and 1979-1981 model years.