Ram 2500 Brake Bulb Size

Additional Notes

• The Ram 2500 brake light circuit relies on dual-filament bulbs across all listed model years, a design that allows a single housing position to serve both the running light and the stop light functions through separate filaments operating at different wattages.
• The 3057 and 3157 are both T25 wedge bulbs rated at 12V with a 27W high filament and a 7W low filament, making them physically similar, though they are not confirmed as interchangeable in these specifications. The Ram 2500 (2013-2018) uses the 3057 exclusively under the condition that projector-type headlamps are absent.
• The 2019-2020 Ram 2500 shifts to the 3157 bulb, but only under the condition that halogen capsule headlamps are fitted, indicating that the brake bulb fitment on those model years is tied to the vehicle's headlamp configuration.
• The 2023-2024 Ram 2500 uses the 1157 for the brake light position. Unlike the T25 wedge types used in earlier years, the 1157 uses a BAY15d bayonet base, meaning it is not physically compatible with sockets designed for the 3057 or 3157.
• The 1157 operates at 12V with a 21W high filament and a 5W low filament, which represents a lower wattage output on both filaments compared to the 3057 and 3157 used in prior model years.
• The center high mount stop light on the Ram 2500 uses the 921 bulb across all listed model years from 2011-2024, with no variation tied to headlamp type or trim configuration.
• The 921 is a single-filament T15 wedge bulb rated at 12V and 16W, a specification consistent with its dedicated stop-light-only role in the center high mount position, where a dual-filament design is not required.
• All bulb types listed for the Ram 2500 conform to ANSI standards applicable in both the United States and Canada, indicating cross-border parts compatibility within those two markets.