The Peterbilt 227 uses a 194 bulb size for front side marker applications and an 1816 bulb size for rear side marker applications. The replacement chart covers 1990 to 1994 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 Peterbilt 227 uses two distinct bulb types across its side marker positions for the 1990-1994 model years: the 194 at the front and the 1816 at the rear.
Both the 194 and 1816 are ANSI-standardized miniature wedge bulbs rated for 12-volt electrical systems, making them compatible with standard North American automotive wiring.
The 194 bulb follows the T10 form factor and draws 3.78 watts, placing it among the lower-wattage options in the miniature wedge category.
The 1816 bulb uses the T3.25 form factor, which is physically smaller in tube size than the T10, and operates at 4 watts.
Although the 194 and 1816 share the same wedge-base connection type, their T10 and T3.25 housings are not interchangeable due to differing physical sizes.
The wattage difference between the two bulbs is marginal at approximately 0.22 watts, yet substituting one for the other is not supported by the fitment data for the Peterbilt 227.
Both bulb types carry ANSI standardization applicable to both the United States and Canada, reflecting their use in North American commercial vehicle markets.
The front side marker position on the Peterbilt 227 specifies the 194 bulb consistently across all five model years covered in the specifications.
The rear side marker position specifies the 1816 bulb with equal consistency across the same 1990-1994 span.