Cadillac Escalade EXT Turn Signal Bulb Size

Additional Notes

• The Cadillac Escalade EXT uses T25 wedge-base bulbs across all listed front and rear turn signal positions for every model year in the specifications, making the T25 wedge the universal base type for this vehicle's turn signal system.
• All bulbs listed in the specifications conform to ANSI standards applicable to the US and Canadian markets, and all operate at 12 volts, consistent with standard automotive electrical systems.
• The "NA" suffix present on all front turn signal bulb designations denotes natural amber glass, meaning the amber color is built into the glass envelope itself rather than produced by a clear bulb inside an amber lens housing.
• The rear turn signal bulbs across all listed years carry no "NA" suffix, indicating they use clear glass envelopes, which is typical when the lens housing itself provides the amber coloring.
• Dual-filament bulbs, such as the 3457NA, 3157NA, 3057, and 3157, operate at 27W on the high-intensity filament and 7W on the low-intensity filament, allowing a single bulb to serve both turn signal and parking light functions simultaneously.
• The 3357NA used in the 2013 and 2010 Cadillac Escalade EXT front turn signal position is a single-filament bulb rated at 27W, unlike the dual-filament 3457NA and 3157NA used in other years, which affects whether the position can serve a secondary lighting function.
• The 3047 rear turn signal bulb used in the 2011-2013 model years is also a single-filament unit rated at 27W, distinguishing it from the dual-filament 3057 and 3157 bulbs used in earlier years at the same position.
• Because the 3357NA and 3457NA are both T25 wedge bulbs with natural amber glass at 12V, their physical form is identical, but substituting one for the other changes the filament configuration, which affects whether the socket position supports a dual-function role.
• The front turn signal position of the Cadillac Escalade EXT used four distinct bulb types across the 2002-2013 production span, specifically the 3157NA, 3757NA, 3457NA, and 3357NA, none of which are interchangeable without accounting for filament count differences.
• The 3757NA used in the 2007-2008 front turn signal position shares the T25 wedge base and natural amber glass with other front turn signal bulbs in the specifications, but its wattage is not listed, unlike the explicitly rated 3157NA and 3457NA variants.