The Pontiac Montana uses 194 bulb size for front side marker applications and either 194 or 3057 bulb sizes for rear side marker positions. The replacement chart covers vehicle production spanning 1999 to 2006 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 194 bulb is an ANSI-standard miniature wedge type with a T10 form factor, rated at 12 volts and 3.78 watts. It is recognized under both US and Canadian standards.
The 3057 bulb is an ANSI-standard dual-filament wedge type with a T25 form factor, rated at 12 volts with a 27W/7W output split between its two filaments. It is also recognized under both US and Canadian standards.
The dual-filament design of the 3057 means it supports two independent brightness levels within a single bulb, which is a characteristic associated with combined stop and tail light functions.
The Pontiac Montana uses the 194 bulb across all model years from 1999-2006 for the front side marker position without exception.
The rear side marker position on the Pontiac Montana does not use a single bulb size across all model years. The 194 and 3057 are each specified for different years in that position.
The 3057 bulb is specified for the rear side marker on the 2002-2004 Montana, representing a departure from the 194 used in earlier and later model years for that same position.
For the 2005 Montana rear side marker, the 194 bulb is specified only on vehicles with four headlamps, indicating that headlamp configuration is a relevant fitment variable for that year.
The T10 and T25 designations refer to the tubular bulb body width, with T25 being physically larger than T10. These two bulb types are not interchangeable due to differences in size, wattage, and filament count.