The Peterbilt 270 front and rear turn signal bulbs both require a 2057 size bulb for proper operation. The replacement chart covers vehicle production spanning 2001 to 2003.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 2057 is an ANSI-standardized bulb type recognized across the United States and Canada, making it a widely available replacement in the North American market.
As a dual-filament bulb, the 2057 supports two independent brightness levels within a single housing, which allows it to serve both turn signal and secondary lighting functions simultaneously.
The 2057 uses a BAY15d bayonet base, a two-pin offset base design where the two pins are positioned at different heights to prevent incorrect insertion during installation.
The Peterbilt 270 uses the 2057 bulb for both front and rear turn signals across the 2001-2003 model years, meaning a single bulb type covers all four turn signal positions on the vehicle.
The 2057 operates at 12 volts, consistent with standard automotive electrical systems.
The two filaments in the 2057 draw 26.9 watts and 8 watts respectively, with the higher-wattage filament typically associated with the active turn signal function and the lower-wattage filament used for a reduced-intensity mode.
The 2057 is described as a brighter variant of the 1157 bulb. While the two types share the same BAY15d base and are physically interchangeable in many sockets, the 2057 produces greater output on its high-intensity filament, which can affect compatibility in housings calibrated for the 1157.