Chevrolet Classic Courtesy Bulb Size

Additional Notes

• The T10 miniature wedge is the bulb type specified for the courtesy function of the Chevrolet Classic across the 2004-2005 model years.
• The T10 form factor uses a wedge-style base, meaning the glass envelope itself acts as the retention mechanism rather than a separate metal base or pins.
• The 168 designation follows the ANSI standardization system, which applies to both the United States and Canada, indicating a consistent part number across North American markets.
• The 168 bulb operates at 12 volts, which is consistent with the standard electrical system voltage found in passenger vehicles.
• At 4.9 watts, the 168 bulb draws a low level of current, a characteristic typical of interior courtesy lighting applications where extended illumination without significant battery drain is expected.
• The T10 designation refers to the bulb's tubular envelope, with the numeric portion indicating a width of 10 eighths of an inch, a sizing convention used in the ANSI miniature bulb classification system.
• Because the 168 is an ANSI-standardized type, it is physically interchangeable with other bulbs sharing the T10 wedge base, though substitutions with different wattage ratings may affect circuit compatibility.