The GMC K1500 Suburban side marker utilizes a 194 bulb size for illumination purposes. Data for the specified lighting component covers the range from 1995 through 1999.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The GMC K1500 Suburban relies on two bulb types across its side marker positions: the 194 and the 168. Both are ANSI-standardized miniature wedge bulbs sharing the T10 form factor and a 12-volt operating voltage.
Although the 194 and 168 share the same T10 wedge base, they are not interchangeable. The 168 draws 4.9 watts while the 194 draws 3.78 watts, meaning the two differ in power consumption despite their physical similarity.
The T10 designation refers to a tubular bulb with a width of ten thirty-seconds of an inch. The wedge base design requires no separate metal socket pins, as the glass envelope itself acts as the retention mechanism within the housing.
Front side marker positions on the GMC K1500 Suburban used the 168 bulb from 1979-1986, then transitioned to the 194 bulb from 1992-1999.
The rear side marker positions on the GMC K1500 Suburban used the 194 bulb across all listed years, spanning 1979 through 1999.
The 194 bulb is specified for both front and rear side marker positions on the K1500 Suburban from 1992-1999, making it the sole side marker bulb type required for vehicles from those model years.
The front side marker on the 1979-1986 K1500 Suburban required the higher-wattage 168 bulb, while the rear side marker on those same vehicles used the lower-wattage 194 bulb, meaning front and rear positions were not served by the same bulb during that period.
Both the 194 and 168 carry ANSI standardization recognized in both the United States and Canada, indicating consistent part availability across North American markets.