Ford F-550 Super Duty License Plate Bulb Size

Additional Notes

• The Ford F-550 Super Duty uses two bulb sizes across its license plate lamp positions: the 168 and the 194, both of which are ANSI-standardized miniature wedge bulbs of the T10 type rated for 12-volt automotive electrical systems.
• Although the 168 and 194 share the same T10 wedge base and 12V rating, they are not electrically identical. The 168 draws 4.9W while the 194 draws 3.78W, meaning the two types carry different wattage ratings and are not interchangeable without accounting for that difference.
• The 168 bulb applies to the Ford F-550 Super Duty for the 1999-2010 model years, then again for 2017-2019 and 2021-2022.
• For the 2017-2019 model years, the 168 bulb size is specified only for vehicles equipped with Halogen Capsule Headlamps, indicating that headlamp configuration is a determining factor in the correct license plate bulb fitment for those years.
• The 194 bulb applies to the 2011-2016 model years, representing a period during which the lower-wattage T10 wedge was the specified fitment for the license plate position.
• Both the 168 and 194 are governed by ANSI standards applicable in the United States and Canada, placing them within a widely recognized classification system used across the North American automotive parts market.
• The T10 wedge base format used by both bulb types is a single-contact design where the bulb is retained by the tension of the socket walls rather than a bayonet or screw mechanism, which is a common construction for low-wattage auxiliary lighting positions.