Freightliner Cascadia Brake Bulb Size

The Freightliner Cascadia brake component utilizes a 1157 bulb size for the specific lighting application mentioned in the provided technical data. Information provided covers the time range from 2008 through 2017.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2008-2022	1157

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157

Other Locations

Additional Notes

The Freightliner Cascadia uses the 1157 bulb size across all listed brake light applications from 2008-2022, making it the sole bulb type present in these specifications.
The 1157 is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope. One filament operates at 21W for the brake/stop function, while the other operates at 5W for the tail light function.
The 1157 uses a BAY15d bayonet base, a two-pin offset base design. The offset pin placement is a deliberate anti-misfit feature that prevents incorrect bulb insertion.
The 1157 operates on a 12V electrical system, which is the standard operating voltage for the brake light circuit on the Cascadia across the listed years.
The 1157 conforms to ANSI standards and is recognized in both the United States and Canada, reflecting a standardized specification shared across North American markets.
Because the BAY15d base uses offset pins, it is not interchangeable with the similarly sized BAY15s base, which is a single-filament variant. Substituting a single-filament bulb in a dual-filament socket would result in loss of either the brake or tail light function.