The Cadillac Calais front side marker bulb uses a 194NA size, while rear side marker applications accommodate 194, 168, or 1895 bulb sizes. The replacement chart covers 1968 through 1976 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 front side markers on the Cadillac Calais for 1974-1976 use the 194NA bulb, a T10 miniature wedge type rated at 12V and 3.78W. The "NA" designation indicates natural amber glass, meaning the bulb produces an amber output without relying on a colored lens.
The 194 and 194NA share the same T10 wedge form factor, voltage, and wattage ratings. The sole distinction is that the 194NA carries a factory-tinted amber envelope, while the 194 is clear glass.
Because the 194 and 194NA are physically identical T10 wedge bulbs with matching electrical ratings, a substitution between the two is mechanically possible. However, swapping a clear 194 into a position specified for the 194NA would alter the emitted light color unless the housing lens provides its own amber filtration.
The rear side markers on the Cadillac Calais for 1974-1976 use the clear 194 bulb rather than the 194NA, indicating that amber color output for those positions is handled by the lens or housing rather than the bulb itself.
The rear side marker specification for 1971-1973 shows a change in bulb type. The 1971 model year uses the 194, while 1972-1973 use the 168. Both are T10 miniature wedge bulbs operating at 12V, but the 168 draws 4.9W compared to the 3.78W of the 194, making them electrically distinct despite sharing the same physical base type.
The 1968 Cadillac Calais rear side marker uses the 1895, a T5 miniature wedge bulb rated at 12V and 0.9W. The T5 form factor is physically smaller than the T10 used in all other positions listed, and the wattage is substantially lower, making it incompatible with sockets designed for T10 bulbs.
The 1895 bulb specified for the 1968 rear side marker position operates at 0.9W, which is considerably lower than any other bulb in these specifications. This reflects the lower luminous output typical of very early side marker applications before federal lighting standards were fully standardized.
All four bulb types listed across these specifications conform to ANSI standards applicable in both the United States and Canada, placing them within a shared North American regulatory framework for miniature automotive lighting.