The Dodge D350 front turn signal uses bulb sizes 2057NA, 2057, or 1157, while the rear turn signal requires either 2057 or 1157 bulb size. The replacement chart covers 1981 to 1993 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 Dodge D350 front and rear turn signals draw from three bulb types across the 1981-1993 model range: the 1157, 2057, and 2057NA, all of which conform to ANSI standards recognized in both the United States and Canada.
All three bulb types share the BAY15d bayonet base, a dual-contact offset-pin fitting that physically distinguishes it from single-filament bases and ensures a secure, polarity-aware connection in the socket.
The 1157 is a dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, where the high filament serves the turn signal flash function and the lower-wattage filament serves a secondary role such as running light duty.
The 2057 and 2057NA are both rated at 12V with a 26.9W high filament and an 8W low filament, making them brighter than the 1157 on both filaments while retaining the same BAY15d base.
Because the 2057 and 1157 share the BAY15d base, they are physically interchangeable in the socket, but their wattage ratings differ, which affects light output and may affect compatibility with the vehicle's turn signal flasher relay.
The 2057NA is the natural amber glass version of the 2057, meaning the amber color is produced by the glass envelope itself rather than by a coated or painted lens, which is a distinction relevant when the housing uses a clear lens.
The Dodge D350 front turn signal used the 1157 from 1981-1990, with the exception of 1991 and 1993, which specified the 2057NA, and 1992, which specified the standard 2057.
The rear turn signal on the Dodge D350 shows less consistency across years, with the 2057 appearing in 1983, 1990, 1992, and 1993, while the 1157 was specified for the remaining years in the range, and 1991 returned to the 1157 despite the front using the 2057NA that same year.
The front and rear turn signals do not always share the same bulb type within a given model year, as seen in 1991, where the front specifies the 2057NA and the rear specifies the 1157, indicating that the two positions are not necessarily interchangeable without confirming the year-specific fitment for each location.
The 1157 is the most frequently specified bulb across both positions and the full 1981-1993 span of the D350 turn signal data, appearing in the majority of front fitments from 1981-1990 and in most rear fitments outside of the years where the 2057 was called for.