The Peterbilt 372 front and rear turn signal bulbs use either 198 or 2057 size specifications. The replacement chart covers vehicle production spanning 1989 to 1995 with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 2057 bulb is the most frequently specified size across both the front and rear turn signal positions on the Peterbilt 372, appearing in the majority of model year entries from 1989-1995.
The 2057 is a dual-filament bulb with a BAY15d bayonet base, operating at 12V with a high-filament draw of 26.9W and a low-filament draw of 8W, making it suitable for combined stop and turn signal functions.
The 2057 is noted as a brighter variant of the 1157, meaning the two share the same BAY15d base type but differ in light output, and the two are not directly interchangeable without accounting for that difference.
The 198 is a miniature wedge bulb of the T5 type, rated at 12V and 2W, which places it in a significantly lower power class than the 2057.
Both the 198 and 2057 conform to ANSI standards applicable in the US and Canada, indicating standardized electrical and physical specifications for each type.
On the Peterbilt 372, the front turn signal for the 1995 model year requires either a 198 or a 2057 depending on headlamp configuration, with the 198 specified for the four round headlamp variant and the 2057 for other configurations.
The same configuration-dependent split applies to the 1991 front turn signal, where the 198 is listed for the four round headlamp variant and the 2057 serves as the standard fitment.
Rear turn signal fitment on the 1994 model year similarly diverges by headlamp type, with the 198 assigned to the four round headlamp configuration and the 2057 to the standard configuration.
The 1993 rear turn signal introduces a third configuration variable, specifying the 198 for vehicles equipped with halogen capsule headlamps, while the 2057 applies to other builds.
The 1989 rear turn signal specifies the 198 for the four rectangular headlamp configuration, indicating that headlamp type is a critical factor in determining the correct rear turn signal bulb for that year.