Chevrolet Silverado Brake Bulb Size

Additional Notes

• The 921 bulb, a T15 wedge type rated at 12V and 16W, serves as the center high mount stop light across all Chevrolet Silverado model years covered in the specifications, from 1999-2024, making it the most consistently used bulb in this dataset.
• The 7443 and 7444 are both T20 dual-filament wedge bulbs rated at 12V, 21W/5W, and share identical electrical characteristics. The 7444NA variant used in the 2024 Silverado carries the same ratings but features natural amber glass, distinguishing it physically from the clear 7444.
• The 3157, used in the Silverado from 1999-2006, is a T25 dual-filament wedge bulb rated at 12V, 27W/7W. It operates at higher wattage than the T20 series bulbs that replaced it in later model years.
• The 3047, used from 2007-2013 and in the 2014 Silverado 2500/3500 HD, is a single-filament T25 wedge bulb rated at 12V, 27W. Unlike the 3157 it succeeded, the 3047 has only one filament, meaning it does not support a separate low-intensity running light function from the same bulb.
• The 2014 Chevrolet Silverado requires different brake bulbs depending on trim: the 1500 uses the 7444, while the 2500 and 3500 HD use the 3047, making sub-model verification necessary for that year.
• The 2021 Silverado similarly splits by sub-model, with the 1500 and 3500 using the 1157 and the 2500 HD using the 7443. The 1157 uses a BAY15d bayonet base rather than a wedge base, making it physically incompatible with wedge-socket housings.
• The 7443 and 7444 share the same T20 wedge form and 12V, 21W/5W ratings, but they are not confirmed as interchangeable within these specifications, as different model years are assigned one or the other distinctly.
• From 2015-2023, the Silverado brake light specifications shift entirely to T20 wedge bulbs (7444 or 7443), moving away from the T25 series that was standard through 2013.
• The 921 center high mount stop light specification for 2022 is noted only for the 2500/3500 HD, while all other years carry no such sub-model restriction for that position.
• The 1157, appearing only in the 2021 Silverado 1500/3500 brake light position, is the sole bayonet-base bulb across the entire specification set, with all other positions using wedge-base designs.