International 7600 front turn signal bulbs use 3157NA size while rear turn signal bulbs use 3157 size. The replacement chart covers 2009 through 2017 production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The International 7600 uses the 3157NA bulb for the front turn signal across all listed model years, 2009-2017.
The rear turn signal on the International 7600 uses the 3157 bulb across the same 2009-2017 span.
Both the 3157NA and 3157 are dual-filament T25 wedge bulbs rated at 12V with a 27W high-filament and 7W low-filament output, conforming to the ANSI standard used in the US and Canada.
The dual-filament design allows a single bulb to serve two lighting functions, typically combining turn signal and parking or running light duties within one housing.
The key distinction between the two bulb types is the glass envelope: the 3157NA features natural amber-tinted glass, while the 3157 uses clear glass.
Because the 3157NA produces an amber output through its tinted glass rather than through a colored lens, substituting a clear 3157 in the front position could alter the emitted light color if the housing lens is also clear.
Both bulbs share the same T25 wedge base and identical electrical ratings, meaning they are physically interchangeable, though the color output difference is a relevant fitment consideration for the front position.
The consistent bulb specification across all nine model years indicates that a single bulb type covers the full 2009-2017 production range for each respective position, front and rear.