Chevrolet City Express front turn signal bulbs use 3457 size while rear turn signal bulbs use 3157NA size. The replacement chart covers 2015 to 2018 production years with bulb specifications for each position.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Chevrolet City Express uses the 3457 bulb for the front turn signal across all model years from 2015-2018.
The 3457 is a dual-filament wedge bulb classified under the T25 form factor, rated at 12V with a wattage split of 27W for the high-intensity filament and 7W for the low-intensity filament.
The dual-filament design of the 3457 allows it to serve two lighting functions within a single housing, which is common in front turn signal applications that also handle parking light duties.
The rear turn signal on the City Express (2015-2018) uses the 3157NA bulb across all listed model years.
The 3157NA shares the same T25 wedge form factor, 12V operating voltage, and 27W/7W dual-filament configuration as the 3457, but is distinguished by its natural amber glass envelope.
The natural amber glass of the 3157NA produces an amber output without relying on a colored lens, which is a factor in rear turn signal assemblies that use clear or lightly tinted housings.
Both the 3457 and 3157NA conform to ANSI standards applicable in the United States and Canada, indicating compliance with North American automotive lighting regulations.
Despite sharing the same T25 wedge base and identical electrical ratings, the 3457 and 3157NA are not interchangeable between front and rear positions on this vehicle, as the amber glass coating of the 3157NA is specific to the rear turn signal application.