The Isuzu i-290 turn signal requires a 3757NA bulb size for proper installation and function. Data for the specific component covers the range from 2007 to 2008.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Isuzu i-290 uses two distinct bulb types across its turn signal positions for the 2007-2008 model years: the 3757NA at the front and the 3057 at the rear.
Both the 3757NA and 3057 are ANSI-standardized bulbs recognized in the United States and Canada, and both follow the T25 wedge form factor operating at 12 volts.
The T25 designation refers to a wedge-base bulb with a tubular envelope roughly 25 eighths of an inch wide, a common sizing convention in North American automotive lighting.
Both bulbs carry dual filaments, meaning each supports two brightness levels within a single housing, which is typical for combined turn and running light functions.
The 3057 rear turn signal bulb is rated at 27W for its high-intensity filament and 7W for its low-intensity filament, reflecting its dual-function role in the lighting circuit.
The 3757NA front turn signal bulb is distinguished by its natural amber glass envelope, which produces an amber output without relying on a colored lens or coating on the vehicle's housing.
Because the 3757NA produces its amber color through the glass itself, substituting a clear-glass equivalent would alter the emitted color and may not satisfy turn signal visibility regulations.
Although the 3757NA and 3057 share the T25 wedge base and 12-volt rating, they are not interchangeable between front and rear positions due to differences in wattage rating and glass color.